Investigating the relationship between Iranian EFL learners’ use of language learning strategies and foreign language skills achievement

Abstract This mixed methods study aimed at examining the relationship between EFL learners’ use of language learning strategies and the extent to which they achieved foreign language skills, namely writing, reading, listening, and speaking. The study also sought to identify possible differences between high and low achieving language learners regarding the frequency and type of their language learning strategies. To this end, the Strategy Inventory for Language Learning (SILL) (Oxford, 1990) was administered to 120 Iranian EFL learners. Likewise, a series of semi-structured interviews was conducted to explore their perceptions of the relationship between their use of language learning strategies and the achievement of the four language skills. The results of the qualitative analysis verified those of the quantitative data, and indicated that a substantial majority of EFL learners perceived the use of language learning strategies as advantageous. However, minor discrepancies were observed not only in the frequency of strategies employed by high and low achievers in the learning of writing, reading, listening, and speaking, but also in the type of learning strategies they utilized while learning the four language skills. Furthermore, our results demonstrated that high achievers mostly employed compensation, affective, and cognitive strategies, whereas low achievers drew on social, metacognitive, and memory strategies more frequently than other strategies. This study holds significant implications for EFL teachers to integrate strategy training into their instruction in the classroom. Informed of the repertoire of strategies used by high language achievers, EFL teachers can encourage language learners to use these strategies to enhance their language learning skills.

Abstract: This mixed methods study aimed at examining the relationship between EFL learners' use of language learning strategies and the extent to which they achieved foreign language skills, namely writing, reading, listening, and speaking. The study also sought to identify possible differences between high and low achieving language learners regarding the frequency and type of their language learning strategies. To this end, the Strategy Inventory for Language Learning (SILL) (Oxford, 1990) was administered to 120 Iranian EFL learners. Likewise, a series of semi-structured interviews was conducted to explore their perceptions of the relationship between their use of language learning strategies and the achievement of the four language skills. The results of the qualitative analysis verified those of the quantitative data, and indicated that a substantial majority of EFL learners perceived the use of language learning strategies as advantageous. However, minor discrepancies were observed not only in the frequency of strategies employed by high and low achievers in the learning of writing, reading, listening, and speaking, but also in the type of learning strategies they utilized while learning the four language skills. Furthermore, our results demonstrated that high achievers mostly employed compensation, affective, and cognitive strategies, whereas low achievers ABOUT THE AUTHORS Hamideh Taheri is a Ph.D. candidate in TEFL at the Islamic Azad University, Shiraz Branch. Her main research interests include psycholinguistics, foreign/second language teaching and learning, and educational linguistics.
Firooz Sadighi is a professor of applied linguistics. He has numerous publications in the areas of educational linguistics, syntax, first/ second language acquisition, and second language education.
Mohammad Sadegh Bagheri is an assistant professor of TEFL at the Islamic Azad University, Shiraz Branch. His research works mainly include foreign/second language assessment, e-learning, and second language research methods.
Mohammad Bavali is an assistant professor of TEFL at the Islamic Azad University, Shiraz Branch. He has carried out research mainly in the areas of foreign/second language acquisition, second language education, and dynamic assessment.

PUBLIC INTEREST STATEMENT
Language learning strategies play a pivotal role in EFL learners' second/foreign language achievement. This study aimed at examining the relationship between EFL learners' use of language learning strategies and the extent to which they achieved foreign language skills, namely writing, reading, listening, and speaking. The study also sought to identify possible differences between high and low achieving language learners regarding the frequency and type of their language learning strategies. The data was collected through a self-report questionnaire and a series of semi-structured interviews. The results indicated that a substantial majority of EFL learners perceived the use of language learning strategies as advantageous. However, minor discrepancies were observed in the frequency of strategies and the type of strategies employed by high and low achievers in the learning of writing, reading, listening, and speaking. This study holds significant implications for EFL teachers to integrate strategy training into their instruction in the classroom.

Introduction
Foreign language learning has long been an overriding concern in the educational system in Iran. Defined as how well students have learned what they have been taught or what they are expected to know, language achievement may result in students' higher levels of academic preparation leading to a higher quality of life (Jerald, 2008). Accordingly, demand for English language instruction as a second/foreign language has been reinforced (Verdugo & Flores, 2007) all over the world seeking to improve the academic achievement of English language learners. To best suit their language learners' requirements, teachers carefully organize language teaching tasks and materials. Language teachers instruct their language learners to enable them to develop adequate skills and strategies while learning English. According to Nyikos and Oxford (1993), learners are not always well cognizant of the fact that they can consciously adopt language learning strategies to more rapidly and efficiently learn a foreign language. Skillful teachers always teach language learning strategies (henceforth, LLSs) to learners and help them pursue a variety of appropriate strategies (Oxford, 2003). Educators may accordingly revise their instructional programs and provide learners with a wide range of learning occasions.
Learning a foreign language is a cognitive process characterized by attributes that demand a great deal of effort from learners (Strakova, 2013). Evidently, language learners need strategy instruction to learn how and where to apply learning strategies to improve their foreign language skills. This research addresses language learning strategies with respect to the four language skills, i.e. listening, speaking, reading, and writing skills (henceforth, LSRW) in a foreign language learning context. Armed with these leaning strategies, language learners can effectively promote their learning practices. The findings of the current study contribute to teacher professional development in that it may raise EFL teachers' awareness and knowledge of effective learning strategies.

Theoretical background of LLSs
Language learning strategies emerged in L2 literature for the first time in 1975 (Rubin, 1975) and referred to the "specific actions, behaviors, steps, or techniques" employed by learners (Oxford, 2001, p. 44) aiming to enhance learners' self-reliance, self-determination, and persistence (Allwright, 1990;Little, 1991). Gagné (1985) viewed learning strategies as mental activities serving the purpose of providing learners with directions varying from the comprehension of questions to the provision of answers. According to Monereo, Castelló, Clariana, Palma, and Lluïsa Pérez (2001), learning strategies point to the processes and approaches that are purposefully, coequally, and contextually employed to attend to newly received information and to acquire new contents effectively. In the same vein, Beltrán (1993) defines learning strategies as personal cognitive practices that learners perform in educational settings. All LLSs share the main concepts of self-reliant learning, student-centeredness, and accountability for self-learning. Clearly, they are typically associated with learners' selfcontrol, self-government, and independence (Rose, 2012).
Researchers have put forth different types of classifications for LLSs. Beltrán (1996), for instance, has classified learning strategies into four categories: (1) support strategies including motivation, attitudes, and affect, (2) processing strategies, namely selection, organization, and processing, and (3) knowledge personalization strategies consisting of creative and critical thinking recovery and transfer. Likewise, O'Malley and Chamot (1990) proposed four categories for learning strategies: Cognitive, metacognitive, social, and affective. Oxford's taxonomy, however, has gained the greatest consideration among other classifications.
LLSs are classified by Oxford (1990) into two main categories: (a) those providing direct mental support for language learning including memory, cognitive, and compensation strategies and (b) those providing indirect support for language learning comprising of metacognitive, affective, and social strategies. Memory strategies involve producing mental connections, using pictures and sounds, recollecting, and performing acts. Cognitive strategies are concerned with rehearsing, exchanging messages, examining and deducing, and inventing patterns for the input and output. Compensation strategies have to do with using imagination in receptive skills and with making use of synonyms in productive skills. Metacognitive strategies include such activities as directing students' attention toward specific language activities, planning their learning, and assessing their own learning that helps them monitor their mistakes and evaluate their improvement. Affective strategies assist learners in reducing their tension, motivating them, and controlling their emotions. Social strategies are comprised of asking questions, collaborating with others, and developing a feeling of empathy with others.

Empirical studies on the relationship between LLSs and learning FL skills
A recent shift from teacher-centeredness to learner-centeredness in foreign language teaching and learning resulted from language theories, research findings, and experiences. This expanded the scientific and theoretical knowledge base on how students learn and acquire a foreign language (Moeller & Catalano, 2015). According to Cook (2000), success in teaching emerges from learning. He also adds that there is no use of teaching language lessons if comprehension does not take place, no matter how exciting, enjoyable, or well-made they are. To Oxford (2001), learning styles and strategies may be compatible or incompatible with the teaching methodology. Emphasizing the teaching-learning relationship, Ellis (2005) maintains that the most effective teaching is consistent with learners' well-liked learning techniques.
The great number of studies on learning strategies highlights their significant role in language learners' success (Schmitt, 2002). Many researchers corroborate the potential relationships between learning styles and language learning strategies (e.g., Bromley, 2013;Wong & Nunan, 2011). Learning strategies, as postulated by Ehrman, Leaver, and Oxford (2003) can be effective if they are in conformity with learners' learning priorities. Conducting a mixed method approach study on motivational and learning strategies of Iranian EFL learners, Bagheri, Yamini, and Riazi (2009) revealed that learners make use of the motivational strategies less than learning and volition strategies.
The literature on learning strategies emerged to identify the characteristics of active learning (O'Malley & Chamot, 1990). Good and bad language learners could be distinguished by their use of language learning strategies. In a study conducted by Wong and Nunan (2011), it was found that active learners employed communicative styles and applied learning strategies independently and variously. On the contrary, less active learners relied on the teacher as an authority figure in the classroom and were disposed toward inactivity. Gerami and Baighlou (2011) collected data by administering the SILL to both male (n = 73) and female (n = 127) Iranian university students majoring in TEFL and English Translation. They found that successful learners took on metacognitive while unsuccessful learners opted for cognitive strategies. Strategic learners as claimed by Weinstein and Stone (1996) and Zimmerman (1990) possess metacognitive and self-controlled skills. They employed well-organized strategies to achieve their goals. To Weinstein and Stone (1996), strategic learners are well aware of various learning strategies and can recognize the efficient approaches in obtaining, merging, and applying new information in addition to relating new knowledge to their background information to get a grip on the new content.
According to Stern (1983), proficient language learners possess mastery over (a) the structure, (b) meanings concerning cognitive, emotional, and sociocultural, (c) communicative skills, and (d) creative use of language. He emphasized all the four skills as proficiency requirements. The employment of learning strategies makes language learning environments more learneroriented and helps learners develop higher proficiency and more active skills (Bromley, 2013;Dornyei, 2005;Oxford, 1993).
During the last decades, several studies have been conducted on the relationship between LLSs and foreign language learning. To examine the learners' use of language learning strategies, almost all the studies conducted so far have utilized the strategy inventory for language learning (SILL). Studies by Loret (2011), andTejedor-Tejedor, González Salvador, andGarcía SeñoráI (2008), for instance, demonstrated a significant relationship between learners' learning strategies and their academic achievement. Habók and Magyar (2018) examined the use of LLSs regarding foreign language attitude, proficiency, and general school achievement among lower secondary students (n = 868) in Hungary. Having adopted the SILL for data collection, they found a positive correlation between LLSs and language proficiency. Acoording to Wu (2008), learners' strategy use is primarily specified by their level of proficiency. That is, proficient learners make use of a wider variety of learning strategies than do less proficient ones.
A great majority of the studies conducted to date on the relationship between language skills and language learning strategies have impressively focused on the strategies most frequently utilized by high language achievers (Shirani Bidabadi & Yamat, 2011;Ghafournia, 2014;Moghaddam & Elahi, 2013;Olivares & Fonseca, 2013;Sawaka Kato, 2005). Along the same lines, Al-Qahtani (2013) and Charoento (2016) revealed that proficient learners mostly adopt cognitive strategies, whereas Wu (2008) reported proficient learners' use of metacognitive and social in addition to cognitive strategies. The number of studies conducted in the last two decades denoted that the two most frequently employed strategies were cognitive and metacognitive strategies. The former concerns analyzing and synthesizing materials while the latter has to do with planning and evaluating learning. Affective strategies, by contrast, were found to be least frequently utilized by language learners. This finding is suggestive of less important roles of emotions in learning (Abu Shmais, 2003;Arellano, 1999;Huang & Tsai, 2003;Sheorey, 2008). In a study conducted by Uslu, Sahin, and Odemis (2016), twenty percent of learners' achievement was found to be significantly predicted by LLSs and twenty-three percent by memory strategies per se. They concluded that the learners who relied on memory strategies while learning English appeared to be higher language achievers. EFL learners' language proficiency requires great mastery over all four language skills which can be enhanced and reinforced by the employment language learning strategies. A great number of studies have been so far conducted on different LLSs that are conducive to the achievement of each language skill independently. According to Chamot (1999), Sawaka Kato (2005), and Shirani Bidabadi and Yamat (2011), second language learners overcome their listening problems by manipulating metacognitive strategies. Having collected data through the SILL and Good Language Learner questionnaires, Moghaddam and Elahi (2013) revealed that memory strategies were most frequently used by high achievers of speaking skill while Olivares and Fonseca (2013) maintained that cognitive and compensating strategies are more instrumental in promoting learners' writing ability. Regarding the relationship between LLSs and reading, cognitive and metacognitive strategies were found by Ghafournia (2014) to be mostly utilized by successful L2 readers.
In respect of the differences between high versus low achievers of different language skills, Ping and Luan (2017) conducted a study on 1699 learners in Malaysian tertiary context by utilizing the SILL. Their study manifested medium strategy use of less proficient learners and high to medium strategy use of high proficient learners. In the same vein, Gani, Fajrina, and Hanifa (2015) uncovered a more balanced performance in the utilization of all six LLSs by high achievers in contrast to low achievers for empowering their speaking ability. Moreover, the purposeful and appropriate employment of the learning strategies by high achieving students happened more frequently than low achieving learners who made use of the strategies inappropriately. Developing speaking skill hence requires learners' more awareness and willingness to use LLSs for better achievement.
With regard to writing skill, Alias, Manan, Yusof, and Pandian (2012) investigated the effects of strategy training using Facebook Notes on the learners' strategies use and their academic writing performance. They found out that the use of Facebook Notes as LLS training tool does promote the use of indirect LLSs. On the other hand, Ahangari and Samadian (2014) found out that cooperative learning activities might improve all the components of writing including content, organization, vocabulary, language use, and mechanics of writing.
Differences between good versus bad achievers were reported by scholars to be due to various factors. As Yusuf and Amanda (2008) have pointed out, differences in reading between successful and unsuccessful learners are associated with the time they devote to reading, the number of times they read, and types of strategies they employ. The other low versus high achievers' difference has to do with skipping meanings of unknown words by low achievers while reading which leads to their failure (Syafrizal, 2000). High achievers, in contrast, develop their vocabulary items by reading various sources which result in their success (Weiner & Bazerman, 1988). Creating mental images and knowing the purpose of reading are the other techniques proposed by Oxford (1990) which assist high reading achievers in concentrating on what they are after and in removing distractors (Brown, 2001). Chand (2014), however, found that all LLSs have a weak positive correlation with learners' language proficiency and concluded that one strategy per se cannot exert a robust and direct impact. Studies on successful and less successful learners have proposed that successful language learners are aware of the strategies they utilize (O'Malley & Chamot, 1990), enjoy more repertoires of strategies (Ting, 2006), and employ more strategies throughout their learning (Hamzah & Abdullah, 2009;Wu, 2008).
As it is evident from the studies reviewed above, no studies have thus far collectively compared all the four language skills in terms of their correlation with LLSs. It can be of great benefit to the educators since the skills can easily be compared and contrasted with regard to their correlation with LLSs. This facilitates the promotion of language proficiency that requires the achievement of all language skills conjointly. Further, the findings obtained in this study are contextually different from the findings of the other researches. So the pedagogical implications could be transferable to other similar contexts.
The advantage of our study is that we deployed a mixed methods approach to examine the relationship between LLSs with language skills achievement. Since the interview data reflect students' experience in using strategies to achieve language skills, they can aid educators to get aware of not only the barriers on the way of strategy training and language achievement but also how to remove or modify them. Scarcely emerging in the literature is a research on high versus low achievers' most as well as least frequently employed LLSs in the acquisition of the four language skills. To fill the gap, we attempted to delve into EFL university students' perceptions of the relationship between their use of language learning strategies and the achievement of the language skills in question. The study is thus guided by the following research questions: 1. Is there any significant relationship between EFL learners' use of language learning strategies and their achievement of foreign language skills? 2. What strategies are the language skills mostly correlated with?
3. Are there any differences between high achievers and low achievers regarding their use of learning strategies while learning different language skills? 4. What are the strategies most and least frequently employed by high achievers and low achievers throughout their language skills achievement? 5. What are EFL learners' perceptions of the relationship between their use of language learning strategies and their achievement of foreign language skills?

Methodology
To address the research questions of the present study, a mixed methods approach was utilized. The quantitative data regarding the independent and dependent variables of the study were gathered from the SILL questionnaire which was then analyzed quantitively. Further, a series of semi-structured interviews was conducted to explore EFL learners' perceptions of relationship between LLSs and language skills. Quantitative study analyzes the data by relying on the formalized system of statistics while qualitative study relies on the researcher's individual sensitivity (Dornyei, 2007). Qualitative studies closely inspect relationships, occurrences, conditions, and qualities of data. It also offers appropriate chances to carry out a descriptive study to better understand participants' perspectives on the topic under study (Best & Kahn, 2006;Marshall & Rossman, 1999). According to Dornyei (2007), mixed methods research increases the strengths of the study while eliminating the weaknesses, is appropriate for multi-level analysis of complex issues, improves the validity of the research, and usually reaches a larger audience than a monomethod study would.
It is noteworthy to mention that although the present study is a mixed methods design study, the quantitative part is more predominant than the qualitative part which is obviously used as a supporting part to validate the results generated from the analysis of the quantitative data.

Participants
In the quantitative phase of the study, a total of 120 sophomores (90 females and 30 males) majoring in English literature at the Islamic Azad universities located in Bushehr province in Iran took part in the study. The participants were in the second semester of the academic year 2018-2019. As they had all passed advanced courses in listening, speaking, reading, and writing skills as obligatory courses in BA program, they were mostly regarded as advanced language learners with their ages ranging from 19 to 35. We used convenience sampling method to select the participants. The students' consent was obtained by completing consent forms for this study.
Moreover, 20 students (15 females and 5 males) were selected from among the questionnaire respondents for the qualitative phase of the study. They had previously expressed their willingness to participate in the semi-structured interviews.

Strategy inventory for language learning
The Strategy Inventory for Language Learning or SILL developed by Oxford (1990) was used to assess EFL learners' language learning strategies. As an all-inclusive classification of learning strategies (Ellis, 1994), this inventory was considered to be fit for this study. In additinon, SILL is the most frequently adopted strategy around the world whose reliability and validity have been examined in different ways and in multiple contexts all over the world. This 50-item inventory consists of two parts including direct (29 items) and indirect (21 items) learning strategies. The direct strategies are composed of memory (nine items), cognitive (14 items), and compensation (six items) strategies, while the indirect strategies include metacognitive (nine items), affective (six items), and social (six items) strategies. The SILL is a tool to assess learners' language learning strategies on a five-point Likert scale ranging from (1) always, (2) usually, (3) sometimes, (4) seldom, and (5) never.
The SILL (see Appendix A) was administered to students in two languages, English and Persian. The Persian version was utilized and validated in the context of language teaching in Iran by Akbari and Hosseini (2008), Mohammadi and Alizadeh (2014), Pishghadam (2008), Soodmand Afshar, Sohrabi, and Malek Mohammadi (2015), Tahmasebi (1999), and Tajeddin (2001). For more precision, a professional English translator checked the English translation of SILL before being administered to the participants.

Semi-structured interviews
A series of semi-structured interviews were conducted for cross-validation of the results of the quantitative analyses of the SILL. Interviews, as Richards (2009) puts forth, provide valuable evidence by delving profoundly into the students' apprehension. The interview questions intended to explore learners' perceptions of LLSs and their relationship with language skills achievement. For the purpose of the study, they were translated by the main researcher (first author) and checked by the certified English translator for more accuracy (see Appendix B). The interview questions were pilot-tested prior to conducting the main semi-structured interviews.

Language achievement scores
The third instrument employed in the study included the achievement scores that students obtained in their listening, speaking, reading, and writing courses. Iranian university students majoring in English have to pass courses on all four language skills in the first semesters of their BA program. In the current study, the students' achievement scores on the four language skills were obtained by their teachers based on not only several course-related and teacher-made tests but also their oral participation (specifically for evaluating speaking skill) in the classroom. The tests that English teachers utilized for evaluating their learners had already been pilot-tested on several groups of learners and validated by a number of teachers teaching the same courses. The students' scores were calculated out of 20.

Reliability of the inventory
As a measure of reliability or internal consistency, Chronbah's alpha test was used to estimate the reliability of the SILL inventory. The Cronbach's alpha coefficient of the whole SILL inventory employed in the study was .700. In addition, the internal consistency of the memory, cognitive, compensation, metacognitive, affective, and social strategies turned out to be .768, .707, .768, .825, .808, and .826, respectively. As Cronbach's alpha coefficient of .70 or higher reflects a good degree of reliability (Salkind, 2007), the reliability coefficients obtained confirm the internal consistency of the whole SILL inventory as well as the items pertinent to the memory, cognitive, compensation, metacognitive, affective, and social strategies.

Data collection procedures
The participants were requested to complete the SILL by reading the statements carefully and marking a tick by one of the five options. It took them about 15-20 minutes to fill in the inventory.
For the purposes of this study, language achievement scores in reading, writing, listening, and speaking courses of all the questionnaire respondents were obtained from their teachers.
The semi-structured interviews were performed in the main researcher's (first author's) office. For the ease of communication, the participants' native language (Persian) was used and their consent was obtained to record their voices for further analysis. They were assured that their data would not be traced back to them in the study. Each interview took approximately 10 to 15 minutes. The participants were arranged to be present for the interview at a specified time. The inteviews took almost 4 hours to accomplish. To ensure anonymity and confidentiality, we used S1-S20 (student 1-student 20) and HA and LA (high achievers & low achievers) to refer to their quotations.

Data analysis
In order to analyze the data obtained from the questionnaire, descriptive statistics and inferential statistics were computed using IBM SPSS Statistics 24.
With regard to the semi-structured interviews, thematic analysis was employed to analyze the main patterns within the qualitative data (Dornyei, 2007). First of all, the interview data were transcribed. Then, they were reviewed a couple of times and key terms and phrases were coded. To ensure the inter-rater reliability, the coding analysis was performed by three of the researchers conducting the present study. After semantically analyzing the codes, they were compared and contrasted to extract the themes and sub-themes. The frequently occurring themes were, afterwards, marked and improved over and over. Regarding the purposes of the study, the ultimate themes and subthemes were constituted.
It is worth mentioning that the data gleaned from the interviews were analyzed and coded in Persian. The derived key themes and sub-themes, as well as exemplary interview excerpts, were translated into English by the main researcher (the first author). The certified English translator checked the English translations for issues related to accuracy. In light of the purpose of the study, only the parts of the interview data that were relevant to the study were reported and the irrelevant parts were eliminated. The interview coding scheme is given in Appendix C.

Quantitative phase
Descriptive data of the participants' achievement scores in listening, writing, reading, and speaking obtained from their teachers are illustrated in Table 1. Table 2 depicts the descriptive statistics for the participants' language learning strategies obtained from the questionnaire data.
To determine the normality of the distribution of the variables, the Kolmogorov-Smirnov test was run. It is a nonparametric test of the equality of continuous, one-dimentional probability distributions. Table 3, the p-values were lower than 0.05 (p < 0.05) for all variables (LLSs, memory, cognitive, compensation, metacognitive, affective and social). Thus, owing to the

Research question 1
To investigate the relationship between EFL learners' use of LLSs and their achievement of foreign language skills, the points that students obtained on the SILL inventory items were correlated with their skills achievement scores to show whether there is a positive, negative, or no relationship. In so doing, the Spearman's correlation test was employed. It is a nonparametric measure of rank correlation assessing the relationship between two variables using a monotonic function. The Spearman correlation coefficient ranges from a perfect positive relationship of +1 to no systematic relationship at 0.0 to a perfect negative relationship of −10.
The results are depicted in Table 4.
As presented in Table 4, the correlation between LSRW skills and LLSs was significant at the level of 0.01. Additionally, the Spearman correlation was 0.569 indicating a good correlation. Thus, there was a significant relationship between LSRW skills and LLSs. This denotes that learners' achievement of FL skills enhanced as the use of language learning strategies increased. Table 4 can also help us to answer the second research question. Thus, regarding the strategies which language skills were mostly correlated with, Table 4 indicates that listening, speaking, and writing skills were mostly correlated with the compensation strategy. However, the reading skill, as the table illustrates, was mostly correlated with the cognitive strategy.

Research question 3
The third research question addressed whether there were any significant differences between high achievers and low achievers regarding their use of learning strategies while learning different language skills. In order to answer this question, two levels of students' achievement, high and low, were taken into consideration. So the participants were divided into two groups. Those who had obtained a higher score in achieving listening, speaking, reading, and writing skills were selected as the high achieving group and those with a lower score in language skills achievement were chosen as the low achieving group. In so doing, all four skills were comprehensively attended to.
To answer this question, the sum of ranks for LLSs used by high and low achievers was computed followed by the Mann-Whitney U test. It is a nonparametric test used to compare differences between two independent groups when the dependent variable is either ordinal or continuous. The results are displayed in Tables 5 and 6, respectively. .000 .001 .000 .000 .000 **. Correlation is significant at the 0.01 level (2-tailed). *. Correlation is significant at the 0.05 level (2-tailed). Table 5 illustrates the most and the least frequently utilized strategies by high achieving versus low achieving students. It manifests that upper-level students mostly employed cognitive strategies while lower-level students used social strategies for skills achievement. The table also indicates that social and affective strategies were least frequently utilized by high achievers and low achievers, respectively.
The results of the Mann-Whitney U test as portrayed in Table 6 indicate that there was a significant difference between high achievers and low achievers (p < 0.05) regarding all LLSs except the social strategy. This suggests that high achievers and low achievers were statistically different. In other words, they employed different strategies while acquiring listening, speaking, reading, and writing skills. Additionally, high achievers made use of strategies much more frequently in comparison to low achievers who utilized the strategies less frequently. Thus, students with high performance and those with low performance were quite different regarding the type of strategies they employed and the frequency of their use.

Research question 4
The fourth research question investigated the strategies most and least frequently employed by both high and low achievers for better achievement of listening, speaking, reading, and writing skills independently. In so doing, the sum of ranks for LLSs used by high and low achievers was computed followed by the Mann-Whitney U test. The strategies that were most and least frequently employed by the two groups of EFL learners for achieving listening skill are illustrated in Table 7.
As depicted in Table 7, high achievers employed compensation strategies and cognitive strategies most frequently for their listening activities while low achievers made use of social strategies most frequently. On the other hand, the least frequently utilized strategies were found to be social strategies and compensation strategies by high achievers and low achievers, respectively. Thus, the two groups employed conversely different strategies while acquiring the listening skill. Table 8 presents the frequency use of the LLSs by high achievers and low achievers throughout their speaking skill achievement. As Table 8 illustrates, compensation strategies as well as affective strategies were mostly utilized by language learners with high speaking performance, while social strategy was found to be most frequently employed by students with low speaking performance. Following Table 8, the social and compensation strategies were least frequently utilized by high and low language achievers, respectively. Clearly, these two groups were quite opposite with regard to the type of strategies they utilized during speaking activities. Table 9 portrays the LLSs utilized for reading by students with strong and weak reading capabilities. Table 9 shows that the LLSs utilized by high achievers were almost conversely different from those employed by low achieving group while practicing speaking activities. In other words, the compensation strategy was found to be most frequently utilized by high achievers and least frequently employed by low achievers. Table 9 also indicates that the utilization of social strategy by low achievers had the highest frequency and metacognitive strategy employed by high  achievers possessed the lowest frequency. The frequency and type of LLSs used by the two groups of high versus low achievers for the achievement of writing skill is manifested in Table 10.
As Table 10 indicates, high achievers utilized memory strategy more frequently than other strategies for achieving the writing skill while low achievers employed affective strategy most frequently. On the other hand, the least utilized strategies were found to be affective and memory strategies for high achievers and low achievers, respectively. Thus, the LLSs were quite conversely utilized by the two groups for writing activities.

Research question 5
To investigate EFL learners' perceptions of the use of language learning strategies for the achievement of foreign language skills, we conducted a series of semi-structured interviews. The data obtained from the semi-structured interview analysis were thematically analyzed. Accordingly, four main themes were uncovered comprising of:  1) The significance of LLSs in achieving FL skills 2) Types of strategies employed for each foreign language skill 3) Factors hindering the utilization of LLSs 4) EFL learners' requirements to promote the achievement of language skills using LLSs (for the interview coding scheme see Appendix C).
4.2.1.1. Theme I. Prior to initiating the semi-structured interviews, the researchers introduced different types of LLSs and their relevant activities and practices. Then they briefly elaborated on the questionnaire items for the interviewees' better apprehension and preparation. The findings obtained from the interview data were reflective of EFL learners' awareness of strategy use in mastering LSRW skills substantiating the findings obtained from the questionnaire data. With regard to the first theme associated with the significance of LLSs in achieving FL skills, almost all the learners agreed on the effectiveness of LLSs in skills achievement. Some interview excerpts clarifying learners' perceptions of LLSs use are presented below.
As the following excerpt indicates, some students emphasized the great variety of LLSs as an advantage leading to higher achievement of language skills, e.g., Well, I think there are different kinds of strategies that we can use to achieve language skills. So if one strategy is not good or I don't know how to use it, I can replace it by another one. I think this helps us solve our problems in learning the skills. (S3)  Nevertheless, some other students reported the applicability of LLSs in different situations as an important factor facilitating skills achievement, e.g., I think if our English teachers train us well, we will be able to use the strategies in different places … inside class or outside class. I believe that we need their help very much mostly as a start but after that we can use them ourselves without any help. It will not matter in which situation we want to use English … or even which skill we use.(S12) Table 11 portrays the sub-themes related to the first theme regarding the importance of LLSs in achieving FL skills.
As the above table indicates, several advantages have been reported by the students to LLSs use in achieving second language skills. 4.2.1.2. Theme II. The second theme drawn from the interview concerned learners' perceptions of the most effective strategy in promoting each language skill that was in accord with the results obtained  from the questionnaire data. To most of the students interviewed, compensation strategies and cognitive strategies were instrumental in promoting foreign language skills. They reported that they compensated for their limitations in foreign language learning by guessing meanings and using gestures (e.g. S2, HA) When I do not know the meaning of a word or expression, I always try to guess its meaning based on the context in which it is used. I never skip unknown words. The data obtained from the interview manifested that all types of LLSs were employed by both high achievers as well as low achievers in acquiring each language skill. The difference, however, lay only in the frequency of use and the type of strategy used for each skill. The following interview excerpts were selected from high and low achieving learners' semi-structured interviews which best clarify their perceptions regarding LLSs use for LSRW skills: A great number of high achievers reported that they employed cognitive strategy for enhancing their reading skill achievement, e.g., When I read English texts, I usually highlight the important parts and make questions. Sometimes when I can't memorize something, I use my imagination. I myself feel that the more I activate my mind, the better I understand … and I can keep the information in my mind for a longer period of time. (S5, HA)  Some other high achievers mentioned affective strategy as the best strategy they utilized while learning speaking skill, e.g., Well, I think that English teachers should be kind. So we will not be stressed. Our teacher tries very hard to make us active in the class. But I see that some students are afraid to talk. I myself feel relaxed in the class. So I take part in any activity in the class. This helps me to be better in English. (S18, HA) A number of other good achievers pointed to memory strategy as a great means of improving their writing skill, e.g., Sometimes I think a lot until I can find a connection between two subjects … . In this way I can understand better and remember better … well this is one way. I believe that if students practice different ways, they can improve their memory. Social strategy was stated by some other low achievers as the strategy they utilized while achieving speaking skill in the class, e.g., Well, I feel that I learn better when I work with my friends or when I ask them questions … I learn many things from them. I feel that I have an important role in the class when we have cooperation. (S7, LA) Table 12 illustrates the type of strategies employed by high and low achieving EFL learners to acquire the four language skills and their percentage of use.
As depicted in Table 12, the three most important strategies used by high achievers for language skills attainment were found to be cognitive, affective, and compensation strategies while the three most significant strategies of low achievers in acquiring LSRW skills were social, metacognitive, and memory-related strategies. This is in line with the data gleaned from the questionnaire analysis.
4.2.1.3. Theme III. The third main theme extracted from the interview data was associated with the learners' insight into the factors hindering their utilization of LLSs for skills achievement. To the majority of students, lack of sufficient instruction was regarded as the most important factor hampering learners' use of LLSs. For example, S4 commented that: I think our teachers' trainings and instructions are not enough. We need more help for using the learning strategies. Most of us still don't know what to do and how to use a specific strategy in different situations. Some of the other interview excerpts drawn from the students' responses to the interview questions are given below.
Some of the students interviewed reported lack of sufficient time as a hindering factor for practicing LLSs, e.g., Oh … Actually, it takes a lot of time when we want to practice some strategies. Our teacher is always afraid she may run short of time. So she only focuses on teaching the texts. It is not important for her to use the strategies. She only wants to finish the book. (S9) Some other students stated that they lacked the necessary awareness of the usefulness of language strategies in learning a second language, e.g., Well, I don't have any idea about these strategies. So I don't use them. Most of us don't know if they are useful in learning English. … . I don't know how to use them for learning each skill. That's why I have lost the chance of learning English by practicing the strategies in the class. I am weak in English now. (S11) The other hindering factor on the way of employing LLSs was reported by some interviewees to be lack of enough background knowledge, e.g., Umm … I think if we want to learn English, we need to have some background knowledge. I see that my classmates don't have the same background knowledge. Some of them are really weak, so they can't work like the other students … . and they remain weak. The students who have enough background information learn better. (S7) Learners' disappointment is a common problem that most second language learners suffer from. That's why a number of students reported lack of motivation as a factor preventing them from using strategies and hence learning the language, e.g., I'm always disappointed about learning English. Actually I don't know why. I think nothing can help me … I have no motivation. So I think even if I use different methods, I can't learn English. So why should I waste my time and energy on practicing the strategies? (S13) The other negative factors reported by the students as hindering the utilization of LLSs are summarized in Table 13.
4.2.1.4. Theme IV. The fourth theme extracted from the interview data was associated with EFL learners' requirements to promote language skills achievement using LLSs. A great majority of students reported needing more instruction and guidance as the main requirement for improving their LSRW skills, e.g., Um … I think our English teacher should train us to use the strategies. Her instruction is not enough. I believe we need her help a lot at the beginning stages, but after that we can use the strategies ourselves without any help … . I mean that little by little we can depend on our own abilities for learning English (S17). Some other interview excerpts given below can better clarify the point: A large number of students commented that LLSs teachers utilize should be appropriate for specific language skills, e.g., I believe that our English teacher should spend much of the class time on training the strategies because they are very helpful for learning English … . Well, actually I think not all the strategies are useful, some of them don't help us at all. We should spend our time on the strategies that are appropriate for learning listening, speaking, reading, and writing. (S2) Some other students pointed to utilizing a variety of strategies, rather than sticking to one or two types for better skills achievement, e.g., Well … we need to practice different kinds of strategies not only two or three. For example, I don't know how to improve my speaking skill because I am familiar with only one or two techniques. They don't help me in my speaking. We have different skills and each skill needs different strategies. (S5) Providing greater opportunities for the students to practice the strategies is the other remark made by some students, e.g., Sometimes I feel that I like to have more time to be able to use the strategies. If our teacher gives us that chance, we can test ourselves and see if we are clear and fluent enough. In this way we learn how to use the strategies in listening, reading, writing, and speaking. (S20) Also, a number of students stated that the patterns used by teachers should be apt for the strategy under consideration, e.g., I learn better when our teacher trains us by first giving examples. So I think if each strategy is trained and used in a good pattern or example, we will learn how to use that strategy correctly for learning English … I mean all the language skills. Well I believe that using more patterns leads to more learning. (S16) Table 14 summarizes EFL learners' main requirements for the LLSs use.
The following tables summarize how each strategy benefits learners in a different way for achieving language skills (Table 15) and how FL teachers and educators should employ appropriate strategies to facilitate learners' learning four different foreign language skills (Table 16).

Discussion
The current study investigated the relationship between language learning strategies and the achievement of the four main language skills i.e. listening, speaking, reading, and writing. Our findings manifested that the students who made use of more strategies were more successful in achieving language skills than those who employed fewer strategies. Both the quantitative as well as qualitative phase of the study proved this positive relationship; that is, learners' achievement of language skills enhanced as the use of LLSs increased. The results also indicated that each language skill was mostly correlated with a specific strategy. In respect of the diversity of LLSs between high versus low achievers for the improvement of LSRW skills, the findings revealed that the two groups employed diverse strategies with different frequency while acquiring the language skills in question. The most frequent strategies employed by high achievers included compensation, affective, and cognitive for listening, speaking, and reading skills. Compensation strategy, however, was replaced by memory-related strategy for writing. Quite differently, low achieving students employed social, metacognitive, and memory strategies for listening, speaking, and reading more frequently than other strategies. For writing, however, affective and cognitive strategies substituted social and metacognitive strategies.
The results obtained from the quantitative, as well as the qualitative phase of the study, demonstrated that a significant relationship existed between Iranian EFL learners' mastery of foreign language skills and their use of language learning strategies. That is, the use of language learning strategies facilitates learners' achievement of FL skills. These findings are congruent with those of Habók and Magyar (2018), Bromley (2013), Al-Qahtani (2013), Charoento (2016), Wong andNunan (2011), andFewell (2010) who revealed that LLSs possess a significant relationship with foreign language learning. One line of explanation could be attributed to the active involvement of learners with language skills while attempting to practice and acquire the relevant tasks in different ways by means of different strategies. Further, as learners make use of various strategies, they are able to overcome different kinds of problems they likely face throughout the learning process.
Although the results of the current study demonstrated a significant relationship between LLSs and almost all the four language skills, some learning strategies enjoyed a higher correlation with certain skills than others did. This implies that each of the four language skills requires different learning strategies. Listening, for instance, possessed the highest correlation with the compensation strategy and the lowest correlation with the social strategy. That is, learners compensated for their limitations in listening comprehension by guessing the meaning and using other clues. This is in contrast with the finding of Shirani Bidabadi and Yamat (2011), who manifested that metacognitive strategies were mostly utilized by L2 learners to develop their listening skill. We found listening to be highly correlated with cognitive, affective, and memory strategies in addition to compensating strategy. Merging several strategies, as Hinkel (2006), Vandergrift (2004), and Goh (2002) pointed out, can be the most efficient practice to improve listening comprehension. Likewise, learners need to actively process the information into meaning that can be paraphrased and recounted (McLafferty, 2015). This can be a difficult task for EFL learners since syntax and vocabulary need to be attended to prior to initiating comprehension process. This accounts for the involvement of several strategies to better achieve listening.
The results of the study also illustrated that the speaking skill was significantly correlated with compensation, cognitive, affective, and memory strategies, with compensation strategy possessing the most correlation. However, a weak correlation was uncovered between the speaking ability and social and metacognitive strategies. These findings are in line with those of Kusumayanthi (2011) and Rachmawati (2015) who found the cognitive and compensation strategies as the most prominent strategies in developing students' speaking skill. Saputra and Subekti (2017) revealed that learners utilized all of the strategies proposed by Oxford (1990) such as memory, cognitive, compensation, metacognitive, affective, and social, yet, they employed the cognitive strategies most frequently.
Consistent with the results of the present study, Barnett (1988), Madhumathi and Ghosh (2012), and Saeedeh (2013) demonstrated a significant relationship between strategies use and reading comprehension. However, our findings did not manifest compatibility with the results obtained by Gürses and Bouvet (2016), Alsamadani (2009), and Mónos (2005, who demonstrated a nonsignificant relationship between reading strategies use and reading comprehension. As far as the results of the study are concerned, reading was most significantly correlated with cognitive strategies followed by compensation and affective strategies. In a similar vein, Pratama, Setiyadi, and Flora (2015), Ghafournia (2014), Khalil (2005) and Su (2005) demonstrated that cognitive and metacognitive strategies were also efficient in the reading comprehension process.
Additionally, the current study revealed that writing possesses a high correlation with compensation and memory strategies, respectively and a low correlation with the other four strategies. This is consistent with the results obtained by Olivares-Cuhat (2002) who found that the use of memory strategy was highly correlated with students' writing achievement, yet in contrast with those of Nasihah and Cahyono (2017), Setiyadi, Sukirlan, andMahpul (2016), andChand (2014) who revealed a significant relationship between writing and metacognitive as well as cognitive strategies.
To justify the extensive use of compensation strategies by language learners as one of our findings, it can be pointed out that owing to the teacher-centeredness of higher education, language learning strategies are not extensively and appropriately attended to by EFL educators throughout their instruction. They draw more considerably on their teaching strategies than learners' learning strategies. That's why EFL learners mostly rely on their abilities to make up for their deficiencies and overcome their language learning problems by manipulating the compensation strategy for skills attainment.
With regard to the strategies employed in acquiring different language skills by high versus low achievers, the present study revealed that there was a significant difference between the two groups in terms of the types of strategies they utilized for learning a specific language skill. High achievers, for instance, most frequently employed cognitive strategies to develop their language skills. This is inconsistent with the results obtained by Rustam, Hamra, and Weda (2015) who reported metacognitive and compensation strategies to be most dominantly employed by high achievers. On the other hand, the current study manifested that low achievers made use of social strategies most frequently to attain language skills. This finding is congruent with the results obtained by Dhanapala (2007). The rationale behind high achievers' frequent utilization of cognitive strategies can be ascribed to their great reliance on their cognition and reasoning abilities which are usually higher than those of low achieving learners. They activate their mind, make use of their imagination, and check their understanding through the context while practicing a specific skill. Low achievers' weak mental abilities and deficient background knowledge, on the other hand, make them rely on teachers and peers' scaffolds e.g., asking questions, working in pairs, and using other social interactions for better comprehension and retention of information.
In line with the results of the present study, O'Malley and Chamot (1990) found that students with higher proficiency were more successful in language task completion owing to the diverse learning strategies they utilized. In contrast, students with lower proficiency made use of fewer and less appropriate strategies resulting in unsuccessful performance. This finding can be justified on the ground that the more learning strategies learners employ, the higher proficiency they are likely to gain. The rationale lies in the fact that each strategy benefits learners in a different way depending on their abilities, interests, and needs which are different among different learners. However, high achievers might gain maximum benefits exploiting a variety of appropriate strategies that conform with their abilities, interest them, and meet their needs with regard to each language skill.
In support of the findings of the study, compensating strategies, as Atlan (2003) demonstrated, could predict learners' achievement of listening, speaking, and reading more robustly than other strategies, emphasizing the utilization of gestures, synonyms, guessing, plausible deduction, authentic communication, handling information gaps, and managing ambiguities for better achievement. Additionally, successful language learners, as described by Rubin (1975), are good guessers. Less successful learners, however, owing to their lack of compensating abilities manipulate other activities such as looking up every unknown word in the dictionary, which might weaken their progress. In the present study, students employing the most compensation strategies were found to be good at receptive and productive skills. Different from other disciplines, language learning is not a cognitive or metacognitive practice per se; rather it is a whole person experience (Oxford & Burry-Stock, 1995) requiring different kinds of appropriate strategies for better and faster attainment of language skills.

Conclusion and pedagogical implications
The present study was undertaken to explore the relationship between EFL learners' use of LLSs and the extent to which they achieve FL skills, namely writing, reading, listening, and speaking. The results indicated a robust positive correlation between LSRW skills and LLSs. The study also manifested that all the six types of strategies were effective in the promotion of each language skill. However, some specific strategies were found to be more crucial in optimizing skills achievement than others. Thus, teachers should take the strategies most frequently utilized by high achievers into account while teaching language skills. This will raise EFL learners' awareness of specific strategies conducive to the improvement of LSRW skills. Building on this, they will be highly motivated to take part in the strategy training activities.With regard to the differences between high versus low achievers, the study demonstrated a significant difference between both groups in terms of the type of strategies they employed as well as the number of times they utilized them for overcoming the problems they face while acquiring FL skills. High achieving learners most frequently employed compensation, affective, and cognitive strategies while acquiring language skills. Quite conversely, low achieving students manifested more tendency towards employing the other three strategies, namely social, metacognitive, and memory. Language teachers are then suggested to focus on the strategies employed by successful learners in the acquisition of each skill to help less successful ones compensate for their shortcomings. In other words, instructors should acquaint low achievers with the significance and effectiveness of LLSs and provide them with the necessary assistance to apply the most appropriate strategies in the process of language learning. To teach more efficiently, instructors need to keep learners abreast of various types of learning strategies.
Low achievers, as the study demonstrated, most frequently made use of social strategies for the attainment of most foreign language skills. This denotes the importance of getting help from others in the language learning process for low achievers instead of relying on their own capabilities as high achievers do. This shortcoming should be taken into consideration by instructors and hence substituted by the most appropriate strategies specifically those utilized by learners with the highest achievement and proficiency levels. In this regard, language teachers can draw on compensating strategies as a helpful means to promote learners' proficiency and to provide them with some new knowledge in the target language as well.
The findings of the current study can be of great assistance to teacher educators and foreign language instructors in several ways. First, they will be aware of the problems on the way of mastering the strategies and achieving the FL such as lack of background knowledge, lack of motivation, lack of sufficient instruction, etc. Second, educators will get acquainted with learners' requirements to promote the achievement of language skills using LLSs such as providing helpful instruction, giving necessary input, asking for cooperation, giving confidence, etc. Third, they could also develop the necessary background knowledge to motivate language teachers to make the best use of LLSs and to employ patterns for more clarity. In so doing, teachers are required to train language learners to draw on effective learning strategies that enhance independent language acquisition. Regarding the integration of LLSs into typical classroom circumstances, EFL teachers are suggested to encourage language learners to attend to specific aspects of new information received, analyze, classify, and expand on the information in the course of data production. On this point, EFL teachers should make learners self-assess their own learning. This would be a surefire way to improve language skills and eventually dispel language learning anxiety.
In addition, the results of the study provide EFL learners with appropriate opportunities to raise their awareness of the significance of LLSs in the promotion of each language skill. The findings also help facilitate the process of foreign language learning by raising learners' knowledge of the strategy types and thereby developing their strategy repertoire. This requires developing learners' awareness, offering reassurance, and providing opportunities for rehearsal. In so doing, learners can take more responsibility for their language learning not only inside but also outside the classroom where there is no educator to help them increase their autonomy.
The results of the current study have this potential to help syllabus designers and material developers design and develop textbooks and materials in which language learning strategies are taken into account. The textbooks thus could acquaint the learners with various types of strategies that must be well trained in order to promote skills achievement of EFL learners.
The most evident limitation noticed in the study is that all the participants selected for this research were from a single context. Lacking variance can significantly obstruct the ability to find significant differences or relationships among the variables under consideration. Therefore, larger and contextually different samples in future research may lead to better results with greater generalizability. Also, different ages and genders should be taken into account to increase the generalizability of the findings.
As a mixed methods study, a series of semi-structured interview was conducted to support the quantitative data. Obsevational data, however, can provide a more objective accounts of events than second-hand self-report data. Future researchers are invited to replicate the study using classroom observation to directly identify the difference between what the students do in the class and what they say they do.

Main Theme
Subthemes Examples (S10) I think if our English teachers train us well, we will be able to use the strategies in different places … inside class or outside class. I believe that we need their help very much mostly as a start but after that we can use them ourselves without any help. It will not matter in which situation we want to use English … or even which skill we use.(S12) Oh … It is clear that if we use different types of strategies for acquiring different language skills, we'll be able to learn them and use them easily. (S18) Well, because of the variety that strategies have the students will not get bored and depressed. It seems to be fun to practice different activities. I myself enjoy using something new. (S 17) If our English teachers train us to use strategies for learning language skills, I think we will not easily forget the materials that they learn, because they will be stored in our mind deeply. (S15) These strategies help us to be able to learn the skills independent of our teachers. We can depend on ourselves. Of course this will be possible if we learn how to apply them well. (S2) strategy is trained and used in a good pattern or example, we will learn how to use that strategy correctly for learning English … I mean all the language skills. Well I believe that using more patterns leads to more learning. (S16) Well, I guess some students need to be motivated. They don't think that learning strategies can be easy. So our English teacher should first give us enough confidence. I think this may help us practice more and learn them better.(S2) I myself always think that the English that they teach us at university is not what is used by its native speakers in real life. Using real materials increases the student' interest in practicing the strategie. (S6) Students learn better if the class is fun. I enjoy practicing something that I like. I think everybody is like this. (S8) Um … .Well I think the more teachers work with us, the more we learn. We should practice the strategies more if we want to learn them well.(S4)