Code Mixing in Online English Classes: A Qualitative Analysis of Teacher-Student Communication at Junior High School Level: Campur Kode dalam Kelas Bahasa Inggris Online: Analisis Kualitatif Komunikasi Guru-Siswa di Tingkat Sekolah Menengah

This study investigates the utilization of code mixing in online English classes at the junior high school level, focusing on the type and frequency of code mixing employed by both the English teacher and students. Data were collected through video recording and observation at SMPN 3 Candi in Sidoarjo, employing a qualitative research design. Muysken's theory (2000) was used to analyze the variation of code mixing in the English class, which included alternation, insertion, and congruent lexicalization. The most prevalent type of code mixing observed was alternation, used as an alternative teaching strategy to enhance student comprehension. The study involved a non-participant observation approach, with data categorized by dates and dialogues classified based on code mixing types. Results indicated that alternation was the dominant code mixing type used by the teacher and students, facilitating improved understanding of English materials. The research concludes that code mixing serves as a valuable pedagogical tool in the learning process, acting as a bridge between students and teachers. The implications suggest further exploration of code mixing in educational institutions and the development of teaching techniques based on the findings to enhance language learning experiences.


Introduction
In Indonesia, English is a foreign language.This language is very important language because English is international language.It has no character of its origin.Although English is a foreign language in Indonesia, there are some people use it as second language.In addition, when the people start to realize how important it is, they try to learn English step by step.Some people start to introduce English since beginning when they have preschool children.In formal education, it is better to introduce English since preschool.For beginners, English can be introduced by vocabularies form.For students, they can learn English easily with the teacher at school in certain time.But they can not be able or master that language and can not apply in daily activity.The obstacle of the students is they only use English at school during English lesson but after that, they use local or daily language.When English teacher teach the material use English language, include explaining the discussed material with the students in class, most of the students can't understand the material given.It is better for the teacher to does not use full of English language in class.Because the limitation of vocabularies of the students.This is happened in SMPN 3 CANDI to the student of grade 9-8 where the English teacher explain the material, the teacher always starts with English and Indonesian as knowledge form even just a little.So that, the students of grade 9-8 get the confusion and do not understand the material that delivered by the teacher.Although some of students can response it.Most of students do not master the vocabularies.
The researchers interest to do the research about code mixing according to phenomenon that happened in social environment or society.where the researchers find the use of code mixing.Even the people who have not t capability of English, they always try to use code mixing to mix two languages, Indonesian and English to communicate with other.[1] The quotation explains that the use of code mixing depends on the condition of society environment, formality, gender or status, and other daily activity.[2] That quotation explains that many factors that influent the use of code mixing in society many times in education, social and culture, economic, etc.The factor that influent the use of code mixing is to make the communication and to know English easily in society environment.And enrich the knowledge of English.[3]It explains that the using of code mixing can be applied in learning English: process because its technic can mix one language to another language for example: English to Indonesia.First Helping the English teacher in explaining English material in classroom, Second Using English dictionary as translated tools in classroom, Third Introducing the English vocabulary and the meaning And the last Doing communication using two languages English -Indonesia to the student.
In this research, the researchers chooses one of English teacher in SMPN 3 CANDI as the research subject.Because the researchers saw that the teacher uses code mixing when delivered the English material to the students in grade 9-8.It makes the researcher interested to know what kind of code mixing that used by English teacher when they explain the English material to their students.And the title of the research is Code Mixing Used by An English Teacher and Students at Junior High School (SMPN 3 CANDI).
Code mixing is the use of two languages.Mix the primary language or mother language with the secondary language.It can be foreign or local language such as Indonesian and English.It can create a new style in language and make it easier in communication [4].Code switching is a process the switching of one code to other code.For example, Indonesian code to English code [5].
Based on the research question are : 1. What types of code mixing are used by the teacher and students in the online class? 2. What is the most common type of code mixing used by the teacher and students in the online classes?

Method
The researchers applied the qualitative research as the design of this research.This method was used because the researchers observed and analyzed how the code mixing was used by English teachers.The researchers did the research on 21st, 24th, and 29th of July 2021 in the SMP Negeri 3 Candi.The research observed and saw the process of the online learning activities.The researcher knew that the English teacher often explained the English material in English and Indonesia.In the video, the English teacher explained the Procedure text for 9 grade materials.The researchers discussed the observation of the video.The researchers did to knew the type of code mixing that used by teacher and students in English class and the most of type of code mixing that used by the teacher and student in English class.
The researchers collected data through observation by using an observation sheet as an instrument.In addition, the researchers videotaped the teacher that taught the English materials in the classroom.This practiced was meant to help the researchers capture the words of teachers and students in the classroom, as well as the limits of researchers when observing.The researchers worked as a non-participant observer, which was not involved in class activities because he merely observed and jot down his observations.In analyzing the data, there were five steps that the researchers did.Firstly the researchers categorized the videos first by their dates.Then, the researchers classified dialogues between teacher and students based on type of code mixing for each video.Afterwards, all the dialogues were compared to the theory that the researchers used, formulated by muysken (2000).Whether they were aligned with the theory.The researchers also wrote a diagram from every types of code mixing to described the pattern of used code mixing.Last we conclude what types of code mixing that were used in the dialogues.

Finding
In this section, the researchers explain that there are many code mixing which occur on the teaching process in the class.there are some code mixing which can be found, that are insertion, alternation and congruent.this type of code mixing which occur will be elaborated with muysken's theory about code mixing.
On the question above, the teacher asks the students to answer question starting with English.Afterwards, the teacher inserts word "Bahasa" which taken from Indonesian Language in the middle of the sentence.At the end, the teacher uses English again to emphasize the question.
Looking through this explanation, the best way to explain this phenomenon is insertion.Insertion occurs when lexical items from one language are incorporated into other language which are reflected on the question above.
Based on the diagram above, 'A' represents English as the question contains 'What, answer please?' and 'it's okay, what?'.While B represent Indonesian as the question has word 'bahasa' in the middle of the questions.Not only teacher's statement which contain code mixing, In students' question also occurs code mixing insertion, as it seen on the question below.
Student: "Breakfast itu, itu yama'am?" In the dialog, the student gives question asking about word which he doesn't know.The question starts with English, then he inserts word 'itu' and 'itu ya', in which taken from Indonesian, in the middle of the question.Similar to previous question, this question is closed with English.As the result of the mixing, the question above can be categorized as insertion.
The diagram above shows that 'A' represents words Breakfast and Ma'am, which is constructed from English while 'B' represents word 'itu, ya' as it is constructed from Indonesian Language.This phenomenon can be categorized as code mixing insertion.Another representation of Insertion occurs in the statement below in which delivered by the teacher.
Teacher: "It's okay ya.Information itu maksudnya yang ada di belakang misalkan, adainstant noodle, instant pasta." As the teacher states 'It's okay,' the teacher begins the explanation to the students using English.While in the middle, he says 'itu maksudnya yang ada di belakang misalkan, ada', signing he mixes the statement with Indonesian Language.At the end of the explanation the teacher inserts English, as he states 'instant noodle, instant pasta.'Looking through this explanation, the type of sentence which is used by the teacher is Insertion.To elaborate this explanation, here is the diagram: Based on the diagram above, 'A' represents English for 'it's okay' and 'instant noodle, instant pasta.' 'B' represents the Indonesian for 'itu maksudnya yang ada dibelakang misalkan, ada.'The teacher inserts the Indonesian words in the middle of the statements.Overall, the three examples which occur on the class are representing Insertion.

Alternation
Code mixing which contains of clauses is called alternation.This code mixing type also appears while teaching, as the example below shows it.
Teacher: "Siapa, your mom?" In the dialogue, the teacher asks to the students who makes the food.From the sentence, we could highlight that there are two languages which forming different clause.The first word, 'siapa' is the Indonesian Language and the teacher uses it as the opening of the question.While the second clause is 'your mom?' which uses English.This phenomenoncan be called Alternation.
Based on the diagram, 'A' symbolized 'siapa' in which an Indonesian word, while 'B' symbolized 'Your Mom' which are English words.But both words relatively separated from each other.This is what Muysken called Alternation.Another example of alternation depicted on the teacher's statement below.
Teacher: "That is the first paragraph, itu tadi pargraf pertama." In the dialog, the teacher informs the students about the first paragraph.It begins using English as he says 'That is the first paragraph,' then continues it with Indonesian by saying 'itu tadi paragraph pertama.'Even though both clauses meet in a sentence, they are remaining separated and not mixed as the second clause translating the first clauses.This explanation leads into the conclusion that the second example is categorized as alternation.Based on the diagram, A symbolized clause 'that is, the first paragraph' in which constructed by English, while 'B' symbolized 'itu tadi paragraph pertama' which are formed through Indonesian language.This shows that the statement categorized as code mixing alternation.Another example of alternation is depicted on the statement below.
Teacher: "And now the second paragraph, paragraph kedua ya, ok." On the example above, the teacher asks the students to move on to the next paragraph, in which the instruction begins with English.Then combine the statement with Indonesian by giving clause 'paragraf kedua ya, ok.'Even though both clause in the same sentence but both remain separated.This is the reason that the teacher's statement categorized as alternation.Another alternation phenomenon occurs below.Alternation: occurs when structures of two languages present in the clause remain relatively separate.
Teacher: "Seperti apa?Misal, misalkan: James lagi choco jam.How to, how to make instant food?" In the dialogue, the teacher gives example of food in front of the students and he gives a question about the procedure to make it.It is clear that at the beginning of the questions the teacher uses Indonesian, then combine it with English as the teacher adds 'choco jam.How to, how to make instant food.'Based on Muysken's theory, that sentence is categorized as alternation because of the sentence's construction contains of two different languages, that are English and Indonesian.
Based on the diagram, 'A' symbolized 'seperti apa missal, missal james' which clearly understandable as Indonesian.'B' symbolized 'choco jam, how to, how to make instant food?' which clearly using English.
While two languages mixed in one sentence, they remain separated.This what makes that sentence categorized as alternation.
Teacher: "Notice join, after English.English lesson please join, join the third lesson.Tolong ya nanti, tolong, ikuti semua pembelajaran hari ini ya." In that dialog, the teacher asks the students to follow the upcoming lesson.As usual, the statement from the teacher is started with English then continue it with Indonesian by giving 'tolong ya nanti, ikuti semua pembelajaran hari ini ya.'The sentence above is part of alternation because of its structure.The structure of this statement uses two different languages that are English and Indonesian.
The diagram shows that 'A' is a symbol for 'notice join, after English, English lesson please.Join, join the third lesson' which is formed from English words, while 'B' is the symbol for 'tolong ya nanti, tolong ikuti, semua pembelajaran hari ini ya' which constructed from Indonesian words.This shows that the teacher's statement above can be categorized code mixing alternation.Another example of alternation which occurs on the class Teacher: "Any question student, mungkin ada pertanyaan?" The dialog occurs when the teacher is about to end the class.It is repeated that the teacher combine two languages to make a question.The clause 'any question student' is formed by English while clause 'mungkin ada pertanyaan?' is formed by Indonesian.Both clauses occurs in a sentence but they are remain separated.
On the diagram above, it is shown that 'A' represents 'any questions student,' in which formed with English words, while 'B' represents 'mungkin ada pertanyaan' which formed with Indonesian words.This is how the code mixing alternation is formed in this statement.
Teacher: "Mungkin ada bumbu bumbu instant." The dialog above occurs when the teacher explains about herbs to the students.In the explanation, the teachers uses Indonesian and English to make students understand.The phenomenon of this is categorized as alternation.The reason of this because the opening of the sentence is using Indonesian, as the teacher says 'mungkin ada bumbu bumbu,' while the end of the sentence, the teacher uses English, as the 'instant'.Because of the meeting od two different languages, this phenomenon can be called alternation.Alternation occurs when structures of two languages present in the clause remain relatively separate.
The diagram shows that 'A' symbolized 'mungkin ada bumbu bumbu' which the words is taken from Indonesian.The 'B' is symbolized word 'instant' which taken from English.This is the prove that the sentence included in code mixing alternation.
Students: "Sereal, maam." In the sentence, the students tell the teacher about breakfast menu which available at home.Similar to the teacher, they use Indonesian to start the conversation, then they put English words at the end as word 'maam' appears.The words which construct the dialog above is part of alternation because there are two words is formed in a sentence and taken from different languages that are Indonesian and English.The diagram shows that 'A' symbolized word 'sereal' which taken from Indonesian, while 'B' is symbolized 'maam' which taken from English word.This is show that the students' statement is categorized as the type of code mixing alternation.

Congruent
This type of code mixing occurs when two languages is combined to make a sentence.Here are one example of congruent which occurs on the first meeting.
Teacher: "The Underline picture, mungkin kalau tidak ada kalian jawab no, kalau ada kalian jawab yes." The data above occurs when the teacher is explaining about picture which appears on exercise.The teacher starts with English as he says, 'the underline picture' then mixed with Indonesian as he says 'mungkin kalau tidak ada kalian jawab.'Not only that, in the middle of the sentence, the teacher use English again and adds Indonesian.Overall, the sentence is built by mixing English and Indonesian with one condition, in which all language should be connected one to another and make a good sentence.
Based on the diagram above, the 'A' represents words in English, that are 'the underline picture', 'no', anf 'yes.'On the other hand, 'B' represents the Indonesian words, that are 'mungkin kala tidak ada kalian jawab' and 'kalau ada kalian jawab'.This shows that the code mixing which applied in this situation is congruent.
In the second meeting, the first code mixing which appear is insertion.This code mixing is containing two components, that are word and clause.Here are the representations of insertion which is found on the meeting 2.
Teacher: "You can write, write down what Diana needs to make breakfast?Pancake, what's the ingridients, bahan bahannya apa saja?Scrambled egg, scrambled egg.
In the dialog, the teacher asks students to rewrite the question correctly.He uses English to begin the questions.Then the teacher slip clause 'bahan bahannya apa saja?" in the middle of the sentence which is an Indonesian sentence.Then, the teacher continues his instruction with English as he says 'scrambled egg, scramble egg.'After breaking down the sentence, it can be seen that this instruction delivered by the teacher is seen as an insertion.Insertion occurs when the lexical items from one language are incorporate into another language.
As the teacher says 'you can write, write down what Diana needs to make breakfast?Pancake' and 'scrambled egg, scrambked egg,' 'A' represents English.On the other hand, 'B' represents the Indonesian words for 'bahan bahannya, apa saja?' Another insertion which occurs is Teacher: "Okay, for students whi just joining the new room, you can do the activity now, just tick true or false, please the statement of human.Jadi, silahkan kalian centangtrue or false this on the statement human.
On the dialog aboce, the teacher asks the students to follow the lesson with video via zoom.The instruction is started with English.Next, the teacher sentence 'jadi silahkan kalian centang' in which it is clearly written in Indonesian.Afterwards, English is used again for the rest of the sentence.Seeing this, it can't be denied that this dialog is categorized as insertion, because in the middle of the sentence there is Indonesian.Insertion occurs when lexical items from one language are incorporate into another language.
Based on the diagram above, 'A' represents the English phrase for 'Okay, for students who just joining the new room, you can do the activity now, just tick true or false please, the statement human' and 'true or false this on the statement human.'On the other hand, 'B' represents the Indonesian clause 'jadi silahkan kalian centang.'The teacher put on the Indonesian words in the middle of the instruction, therefore this is called code mixing insertion.
Teacher: "Okay, a let's discuss together, kita diskusikan bersama ya?The label gives information about noodle, true yeah." In the dialog, the teacher asks the student to discuss about the materials on that day.This instruction is started with English.Then the teacher put sentence 'kita diskusikan bersama ya' in the middle of the sentence.As we know, that sentence is taken from Indonesian words.Afterwards, the teacher continues the instruction with English.Therefore, this instruction is categorized as insertion because it combines two different languages into a sentence.
The diagram shows that 'A' represents 'ok, let's discuss together' and 'the label gives information about noodle, true ya' in which both clauses is using English.Meanwhile, 'B' represents 'kita diskusikan bersama, ya' which construct from Indonesian words and put it in the middle of the dialog.Another alternation which occurs on the second meeting depicts on the dialog below, Teacher: Because it is a fast food ya, karena ini makanan cepat saji ya, so it doesn't take a long time to prepare the noodles."In the dialog quotation above, the teacher shows the students about the type of food which discussed.As he says 'because it is a fast food, the teacher clearly starts the conversation with English.Then, continuing the dialog using Indonesian by saying 'ya karena ini makanan cepat saji ya.' Then the teacher uses English phrase to end the dialogue.This situation makes the sentence categorized as insertion.Insertion occurs when lexical items from one type are incorporate into another language.
Based on the diagram above, 'A' represents English phrase for 'because it is a fast food' and 'so, it doesn't take a long time to prepare the noodle.'On the other hand, 'B' represents Indonesian for 'ya, karena ini makanan cepat saji.'The teachers put on the words in Indonesian in the middle of the dialog.

Alternation
The code mixing which contains of form of clause is called alternation.Here are some alternations which depict on the second meeting.
Teacher: "Five minutes more, lima menit lagi." In the dialog, the teacher reminds the students that the time of students writing questions is end in five minutes.This reminder uses two languages, the first is English and the second is Indonesian.
The English phrase is used to start the conversations.Then, the teacher continues the reminder with 'lima menit lagi' in which clearly using Indonesian.This reminder shows the situation in which two different languages is combined to form a sentence.The language which used are English and Indonesian.In conclusion, this dialog can be categorized as alternation which described as a situation where two different language presents in a clause and both remain separated Based on the diagram, it shows that 'A' is the symbol of 'five minutes more' in which a phrase taken from English.Meanwhile 'B' is the symbol of 'lima menit lagi' which taken form Indonesian words.This technique is called code mixing alternation.Another alternation depicted on the second meeting is seen on the statement below.
Teacher: "This is true or false question ya, jadi ini pertanyaan benar dan salah, salah satu bentuk AKN ya ini ya.Bentuk AKN kan ada pertanyaan benar salah." In the dialog above, the teacher gives the student an example in which started with English.Then he combines it with Indonesian and give sentence 'ya jadi ini pertanyaan benar dan salah, salah satu bentuk AKN ya ini ya.Bentuk AKN kan ada pertanyaan benar salah.'That clause is using Indonesian.
The sentence above is categorized as alternation.It happens because the use of two different language, Indonesian and English, to form a sentence.
Based on the diagram above, 'A' represents the English clause for 'this is true or false,' while 'B' represent Indonesian as it says, 'jadi ini pertanyaan benar dan salah, salah satu bentuk AKN ya ini ya.Bentuk AKN kan ada pertanyaan benar salah.'The teacher put on Indonesian words in the middle of the sentence.

Congruent
Another code mixing which occurs on the class congruent.Congruent is one of code mixing type which should be used in English buat also Indonesian.Here is the representation of congruent.
Teacher: "Finish, ini suara siapa ya,now you can classify.Student from the text ya.Dari teks itu, please calssify stay on the table, silahkan ditulis di table, have you done?" The data shows that the teacher asks the students to make a table based on the text and this instruction is started with English.Afterwards, he continues using some Indonesian words by put on phrase, ini suara siapa ya, dari teks itu, dan silahkan ditulis di table.'Then, the teacher continueswith some Indonesian words and ends the sentence with English as he states 'have you done.
The diagram above shows 'A' represents words in English, that are 'tuhe underline picture,''finish,' 'now you can classify, student from the text, please classify stay on the table, and have you done.' Meanwhile 'B' represents the words in Indonesian, that are 'ini suara siapa ya, ya dari teks itu, and silahkan ditulis di table' dan 'kalau ada kalian jawab.'This is how the form of code mixing congruent.

Code Mixing in Meeting 3 (On 29th of July 2021) Insertion
Code mixing that contains of two components, words, and clause.Here are the representation of insertion.
Teacher: "Loading, masihloading." In the dialog above, the teacher gives the students information in which it starts with English.Then the teacher put on word 'masih' that clearly taken from Indonesian.This word is placed in the middle of the dialog.Afterwards the teacher continues the conversation using phrase which taken from English.As the result of mixing two languages in one sentence, especially put the Indonesian words in the middle of the text, this dialog is categorized as code mixing insertion.The diagram below explains how the insertion works on this sentence.
Based on the diagram above, 'A' represents English words for 'loading,' meanwhile 'B' represents Indonesian words 'masih.'The teacher put the Indonesian words in the middle of the sentence.
Teacher: "Okay the drink will be rotten easily out of the refrigerator, is it fact or no.jadi pertanyaan itu minimum ini akan jadi tidak enak dengan mudah kalo ada di luar kulkas.Yes or no.what is your statement student, it is.I mean it is yes or no what is your answer." In the dialogue above, the teacher gives the student information about a drink.This information begins with English phrase, then the teacher slips Indonesian phrase in the middle of the sentence that is 'jadi pertanyaan itu minuman ini akan jadi tidak enak dengan mudah kalo ada di luar kulkas.'At the end the teacher uses English words to complete the sentence.As the result, this dialogue is categorized as insertion.This happens because in the middle of the sentence there is a phrase which taken from another language.Insertion occurs when lexical items from one language are incorporate into another language.
Based on the diagram above, 'A' represents English phrases that is 'Okay the drink will be rotten easily out of refrigerator, is it fact or no' and 'yes or no, what is your statement student, it is.I mean it is yes or no.What is your answer,' meanwhile the 'B' represents Indonesian as written in the middle of the sentence, 'jadi pertanyaan itu minuman ini akan jadi tidak enak dengan mudah kalo ada di luar kulkas.'The teacher slips the Indonesian words in the middle of the dialog.
Teacher: "Others, its ok you have opinion when if your opinion, your answer no its ok.But give me a reason.Kasih alasannya apa, kalau jawabannyano." In the dialog above, the teacher asks the students to share their opinion.Almost all of the words use English, in the beginning of the sentence and at the end of the sentence.But the teacher inserts Indonesian phrase in the middle of the sentence as he says 'Kasih alasannya apa, kalau jawabannya.' Regarding to this, the dialog which used by the teacher is categorized as insertion.Insertion occurs when lexical items for one language are incorporated into another language.The diagram below explains about insertion based on Muysken's idea.
Based on the diagram, the 'A' represents English phrases such as 'others, its ok you have opinion when if your opinion, your answer no its ok.But give a rason' and 'no.' On the other side, the 'B' represents Indonesians, as it written 'berikan alasannya, kenapa jawaban.'In this situation, it is clear that the insertion of Indonesian words in the middle of the sentence gives impact to the statement and make it categorized as insertion.
In the dialogue, the student gives the teacher a question about the meaning of strictly.Similar to the previous example, this example started with English.Then the students insert words 'itu, apa' in the middle of the sentence, in which it is also an Indonesian word.Afterwards, the students call the teacher ma'am at the end of the statement.It makes the dialog has Indonesian words in the middle of the sentence.
Looking at this fact, the question which delivered by the student is categorized as insertion.
Insertion occurs when lexical items from one language are incorporate into another language.
The diagram shows that 'A' represent English words which occur in the beginning and at the end of the questions that are 'strictly' and 'ma'am.'Meanwhile the 'B' is used to represent Indonesian words that are 'itu, apa.'The teacher is inserting Indonesian words in the middle of the sentence which makes this question categorized as insertion.
Teacher: "No, bisa tidak ini, kan dalam jangka wantu satu hari sajait's okay, yes or no come on." In the statement which the teacher delivered to the students, the teacher begins the statement with English, as he says 'no.' Similar to the previous example, the teacher continues the explanation with Indonesian phrase that is 'bisa tidak ini, kan dalam jangka waktu satu hari saja.'At the end, the teacher states the information with English words.From this explanation, it is clearly seen that this sentence is categorized as insertion.
Based on the diagram, it is clear how 'A' represents English words for 'no' and 'its ok, yes or no come on'.On the other hand, 'B' represents Indonesian phrase for 'bisa tidak ini, kan dalam jangka waktu satu hari aja.'The techer insert Indonesian words in the middle of the dialog.Another example of Insertion occurs below, Teacher: "Still what is your opinion, because a it just have 24 hours.Waktunya hanya, a day, a day, it means 24 hours so, yes or no.What is your opinion." In that dialogue, the teacher keeps trying to ask the students about their opinion.The question which delivered by the teacher starts with English.Then the teacher put on the phrase 'waktunya hanya' in which taken from Indonesian in the middle of the sentence.Like what have been explained before, the teacher continues the sentence using English as he states, 'a day, a day, it means 24 hours so, yes or no.What is your opinion."This explanation leads that this sentence is categorized as an insertion.Insertion happens when the lexical items from one language are incorporated into another language.The diagram below shows how it works: Based on the dialog above, 'A' represents the English phrase 'still what is your opinion, because a it just have 24 hours.'And 'a day, a day it means 24 hours so, yes or no.what is your opinion.'While 'B' represents Indonesian phrase 'waktunya hanya.'The teacher inserts the Indonesian phrase in the middle of the dialog.This quotation said by the teacher below also represents insertion.
Teacher: "If the drink is rotten, you have to hear it soon yes or no.Rotten itu basi tidak enak minumannya,what is your answer yes or no, number 2." In the dialog, the teacher gives the students information that the food is already rotten.This information use English at the beginning and at the end of the dialog, as the teacher says, 'If the drink is rotten, you have to hear it soon yes or no.Rotten …' and 'what is your answer yes or no, number 2.' Then in the middle of that statement, the teacher inserts Indonesian phrase that is 'itu basi tidak enak minumannya.'By inserting Indonesian language in the middle of English sentence, it makes the sentence categorized as insertion.The insertion is happened when one language is incorporated into another language.
Based on the diagram above, 'A' represents English phrase of 'If the drink is rotten, you have to heat it soon yes or no.Rotten' and 'What is your answer, yes or no, number 2.' Meanwhile, 'B' represents Indonesian phrase of 'itu basi tidak enak minumannya.'The teacher inserts the Indonesian phrase in the middle of the sentence which makes it categorized as insertion.

Alternation
Here are the representation of alternation.
Theacher: "Fast full yeah, agak cepat ya." In the dialog above, the teacher asks to write the questions faster.This instruction is written in English at first then he adds Indonesian phrase to complete the instruction.Then the teacher insert Indonesian phrase 'agak cepet ya' at the end of the sentence.This additional phrase from another language makes this instruction can be categorized as Alternation [7].
Based on the diagram above, 'A' symbolized 'fast full more' which clearly use English.Meanwhile, 'B' symbolized phrase 'agak cepat ya' in which the phrase is taken from Indonesian.The mixing of these two languages makes this statement included in one of code mixing type alternation.
Teacher: "Diluar suhu dingin mungkin akan cepat nggak enak enak rasanya, so the answer is yes." In the dialog, the teacher is answering the questions.This discussion is started with Indonesian, then he adds English phrase as he says, "so the answer is yes."By adding different language to complete the sentence, this statement is called alternation.[8] Below is the diagram which can explain how alternation works.
Based on the diagram above, 'A' symbolized 'di luar suhu dingin, mungkin nanti akan cepat nggak enak badan rasanya,' which this phrase is taken from Indonesian Language.On the other hand, 'B' symbolized phrase 'so, the answer is yes' in which formed with English words.However, both language is separate.This makes the sentence is categorized as code mixing alternation.
Teacher: "Yes or no, dalam jangka waktu satu hari saja." Another example of alternation depicts on the statement above.It was when the teacher asked the student to choose the answer based on the questions.The teacher opens the question with English phrase as he says, 'yes or no.' Then finish the rest of the sentence with Indonesian as he says, 'dalam jangka waktu satu hari saja.' Mixing two languages in a sentence makes the teacher's statement become an alternation [9].
Based on the diagram above, 'A' shows the English words 'yes or no,' meanwhile the 'B' symbolized phrase 'dalam jangka waktu satu hari' in which taken from Indonesian.This is how alternation is.Another alternation in the class explains through this quotation, Teacher: "Strictly, itu harus, harus." In the dialog, the teacher explains the students the meaning of one word.The first words appear is 'strictly' in which clearly an English word.Then, the teacher continues the sentence with Indonesian phrase that is 'itu harus, harus.'That words are part of alternation which combining words from Indonesian and English.This situation makes this statement categorized as alternation.
Based on the diagram above, 'A' is symbolized words 'strictly' in which taken from English.On the other hand, the 'B' stands for phrase 'itu, harus itu' which taken from Indonesian words.As the result, this is showing that the teacher's statement is alternation.
Teacher: "Have you done, sudah selesai?" In the dialog above, the teacher asks the students whether they finish everything or not.The question which delivered uses English at the beginning.Then, he combines the question with Indonesian as he says 'sudah selesai?' in which is the translation of the English phrase.This version of the question in which delivered by the teacher is called alternation.It happens because there is combination of English and Indonesian which occurs in one sentence.This conclusion is in line with Mysken's theory about alternation.Alternation occurs when structures of two languages present in the clause remain relatively separate [10].
The diagram above shows that 'A' stands for 'have you done' which a question delivered at the beginning od the question.Meanwhile, 'B' stands for 'sudah selesai' in which taken from Indonesian and the translation of the first question.This is what we called code mixing alternation.Another example of alternation which occurs on the meeting Student: "Masihloading." The dialog above taken from student's statement in which combine 2 words from English and Indonesian.The Indonesian words in the beginning is 'masih' while the English words is 'loading.'Both words complete each other as a sentence to explain the situation of the student.Due to the combination of two languages this is called alternation.Alternation occurs when structures of two languages present in the clause remain relatively separate [11].
Based on the diagram 'A' symbolized word 'masih' in which taken from Indonesian, while 'B' symbolized word 'loading' in which taken from English.This is the type of code mixing alternation.
Teacher: "Tanggal expire." In the dialog above, the teacher tells the students about expired date.The teacher starts the statement with Indonesian word as he says 'Tanggal.' Afterwards, he takes English words to continue his statement by using word 'expire.'This statement is part of alternation because there are two different languages to form a sentence.In this situation the teacher chooses Indonesian and English to build a sentence.By using this step, the teacher has made an alternation sentence in which defined as the meeting two language in a sentence where these languages remain relatively separated Based on the diagram, 'A' symbolizes word 'tanggal' which taken from Indonesian.The 'B' symbolizes word 'expired' which originally English.This is the situation which alternation is formed.

Congruent
Code mixing that should be used not only in English but also in Indonesian.Here is the representation of congruent.
Teacher: "Yes, harus diikuti nanti kalo adaexpire, tanggalexpire." From the data above, the teacher explains the students about the picture which appear on the question and he starts with English by saying 'yes.'Then, he continues the sentence using Indonesian by saying 'harus diikuti nanti kalo ada' and 'tanggal.' Word in English appears again as the teacher mentions 'expired.[12] Based on the diagram above, 'A' represents English sentence for 'the underline picture,' 'yes' and 'expire.' Meanwhile , 'B' represent Indonesian words for 'harus diikuti nanti kalo ada' and 'tanggal.'This is the type of code mixing congruent.

The Types Used of Code Mixing by Teacher and Students in Online Class
Based on the observation by the researcher on 21 st , 24 th , and 29 th of July 2021, [13] The total frequency from the third of that types determine based on the result from population, Discussion of result the types of code mixing can

The Most Common Type of Code Mixing used by Teacher and Students in the online class
Based on the table above, it can be seen that total insertion are 14 , alternation are 17 , congruent lexicalization are 3.And can give a conclusion that common type of code mixing between teacher and student the namely is alternation

Conclusion
The conclusion of the research are: The result of the observation shows the type of code mixing that used by English teacher in SMP 3 CANDI and the students in online class are Insertion, Alternation, and Congruent Lexicalization.But most type used in learning process in class is Alternation.
The result of interview is the English teacher in SMP 3 CANDI often used code mixing type Alternation.Because using two languages because and this type can makes the learning process with the students easier in understanding the English material or assignment given by the teacher.
If the teacher use full English language, the students will not understand about the material.This research show that code mixing which is used in educational institution helps the teacher and students in learning process.Thus, it shows that code mixing is more than just a compound between two or more language used in daily conversation, moreover it has function as a bridge for students and teacher in the learning process.Seeing how beneficial and the function, further research on code mixing used in educational institution needs to be explore more.Further development of the research can be expanded into building teaching technique based on the findings above.

Table 1 .
Is a result of data, and showing total Insertion, Alternation, and Congruent lexicalization

Table 2 .
Is a result data, and showing total Insertion, Alternation, and Congruent lexicalization

Table 3 .
Is a result data, and showing total Insertion, Alternation, and Congruent lexicalization