Digital tildes (“∼”) may convey more: analyzing innovative uses of tildes in Chinese WeChat messages

Innovative uses of punctuation in online communication have become increasingly visible in research and public awareness since the 2000s, whereas studies on the innovative use of tildes (“∼”) in digital use remain scarce. Drawing on a data set of 543 Chinese WeChat messages with sentence-final tildes, this article investigates the uses and functions of innovative tildes in online communication using quantitative data and follow-up interviews. The findings suggest that: (1) The innovative tildes are deployed in messages implying sounds and performing speech acts in online communication, and they are more frequently used in speech acts (e.g., expressives and directives in particular). (2) The innovative tildes convey sound extension, i.e., to compensate for the loss of audio information in online communication and reproduce elongated sounds; pragmatic function, i.e., to enhance or mitigate the illocutionary forces of speech acts; and entertaining function, i.e., to make messages informal, vivid, joyful, and interesting. (3) The innovative tildes are pragmalicalized as a result of their semiotic features and politeness motivation of messengers for maintaining rapport and achieving successful online communication.


Introduction
With text messaging being such a ubiquitous activity (Truss 2003: 195), digital punctuation (Androutsopoulos and Busch 2021) (henceforth, DP)-punctuation in digitally-mediated interaction-is emerging with a divergence from its formal and standard functions in offline texts. This kind of DP use has been variously defined, such as re-purposing traditional marks (Baron and Ling 2011), nonstandard punctuation (Houghton et al. 2018), typographic deviation (Busch 2021), and innovative uses of DP (Androutsopoulos and Busch 2021), etc. We adopt the term "innovative uses", in that DP in this paper will be investigated not "in terms of 'deviation' or 'linguistic rebellion', but as a resource for cooperative mediated interaction" (cf. Androutsopoulos and Busch 2021: 1). Since the 2000s, innovative DP has undergone a process of "pragmaticalization" to convey implicit social and pragmatic meaning as stance indicators (Androutsopoulos 2018;Androutsopoulos and Busch 2021). For instance, the message-final period, which inherently shows that a sentence is complete grammatically and syntactically, is used to indicate a sense of insincerity (Gunraj et al. 2016), consistency of topics, and unwillingness (Androutsopoulos and Busch 2021), etc.
So far, much of the research on the innovative use of punctuation marks in digital communication has been based on periods (".") (e.g., Gunraj et al. 2016;Houghton et al. 2018), exclamation marks ("!") (e.g., Hancock et al. 2007;Waseleski 2006), ellipses ("…") (e.g., Baron and Ling 2011;Hancock 2004;Raclaw 2006), etc. As a matter of fact, a new punctuation in Chinese social media has recently been extensively and actively used-the tilde ("∼"). According to the National Standards of the People's Republic of China (GB/T15834-2011), general rules for punctuation 1 have officially designated the tilde as one of the connection symbols for indicating the start and end of a numerical span or range composed of Arabic numerals or Chinese characters, as shown in example (1). When the tilde is employed for a connection, it is placed between two numerals and pronounced as "dào" (到) or "zhì" (至) in Mandarin, which is equivalent to universal "en dashes", e.g., on pages 45-53.
However, the innovative tildes on social media, different from the above official function, are commonly distributed at the end of sentences. In the following example (2), the sentence-final tilde used by two females' online chats is in place of a question mark and a period to indicate certain tones, which differ in representing spans or ranges in the example (1). The divergence from formal offline texts that is found in digital communication is neither arbitrary nor sloppy (Houghton et al. 2018: 116). Therefore, the current study aims to explore the innovative uses of tildes on Chinese social networks, which has recently been under-researched. (2) The article is structured as follows: Section 2 reviews previous research related to the innovative uses of DP. Section 3 describes the data collection, the analytic framework, and the design of follow-up interviews, followed by the findings in Section 4. In Section 5, we discuss the reasons for innovative uses of tildes online. The final section concludes this study.

Literature review
In the late 1980s, punctuation in digital communication that strayed from norms and standards was one of the distinguishing features of computer-mediated language. After decades of sporadic attention, DP remains a non-systematic and nonmainstream research topic, albeit with a greater frequency of omission and repetition of punctuation marks in computer-mediated communication (CMC) (Bieswanger 2013: 476;Busch 2021: 2;Jonsson 2019: 227). For instance, repeated punctuation marks are used for emphasis (e.g., How did things go yesterday????/oh, my God!!!!) (Murray 1988: 12). Since the mid-2000s, the innovative uses of DP, distinguished from omission and repetition, have attracted researchers' attention. The innovative DP keeps the same form as the standard orthographic norms in offline writing, but redefines or re-purposes its traditional function to convey implicit social, pragmatic, and interpersonal meanings. More common are studies focusing on the innovative uses of digital ellipses. On the one hand, innovative ellipses could be used to convey implicit irony. Hancock (2004) was among the first to observe the interpersonal function of DP. He compared the ironic conversations collected in face-to-face and computer-mediated conversations by English-speaking students through the irony framework. The findings showed that an ellipsis, which originally indicated that a statement was unfinished by omitting one or more words from a sentence (Kirkman 2006: 58), was employed as a cue to signal the ironical intention of CMC speakers. On the other hand, ellipsis could be used as a softer to politely mitigate disagreements (Busch 2021). For example, Ong (2011) conducted a conversational analysis of elliptical turns in multiparty chats among tertiary students in Singapore English and found that the digital ellipses illustrated several turn actions, e.g., signaling disagreement, confusion, and Digital tildes ("∼") may convey more disapproval. In Baron and Ling's (2011) study, they analysed the punctuation frequency in a corpus of text messages sent by American university students and reported that ellipses were used in lieu of 80 % of periods to soften the directness of messages. Similarly, Vandergriff (2013) investigated the pragmatic function of turnmedial ellipses based on the conversational analysis of extracts from task-based conflictual chats among German learners. It was found that turn-medial ellipsis can mitigate disagreement by delaying or avoiding the dispreferred responses.
Two studies provided an analysis of the innovative exclamation marks in English digital interactions. Waseleski (2006), for example, analysed 200 exclamations in online discussion groups for the library and information science profession in a 16-category coding frame. The results suggested exclamation marks rarely served as markers of excitability but might function as markers of friendly interaction. Hancock et al. (2007) also revealed the emotional function of exclamation marks by examining how people express and detect emotions during text-based communication. It was found that comprehenders relied heavily on exclamation marks to figure out how their partner was feeling, as evidenced by the fact that positive users employed approximately six times as many exclamation marks as negative users.
Periods, which are frequently used to denote the conclusion or finality of sentences in offline writing, have also been employed to convey additional pragmatic and social information. Gunraj et al. (2016) examined how people understood and perceived the sincerity of a sentence-final period in short text exchanges in rating tasks. It was discovered that text messages that ended with a period were rated as less sincere than those that did not end with a period. Houghton et al. (2018) replicated and expanded Gunraj et al.'s (2016) experiment and findings. They came to the conclusion that the insincerity of the sentence-final period might be partially attributed to the possibility that punctuating a single word might been interpreted as being excessively formal in the context of an informal text interaction and resulted in the response appearing abrupt (Houghton et al. 2018: 116). Besides this, Androutsopoulos and Busch (2021) found that the sentence-final periods performed more pragmatic functions at the expense of syntactic ones, i.e., indicating the unwillingness to continue a thematic sequence and indexing emotional distance among messengers. This conclusion was reached after analyzing the frequency of German WhatsApp messages containing periods as well as semi-structured group interviews.
Recently, Busch (2021) compared the use of periods, colons, question marks, and ellipses between formal, non-interactional writing in school and informal, interactional writing in WhatsApp, based on a quantitative analysis of German adolescents' text-messaging threads and a close qualitative analysis of message samples. From his analysis, Busch (2021) found that even punctuation signs whose codification in descriptive and prescriptive grammars was based on pure syntactic criteria were used to achieve interactional goals in digital interactions. In other words, punctuation in online communication serves more interactional than grammatical roles. In addition to frequently-used punctuation, several studies have contributed to the innovative uses of less-used punctuation in digital communication. For example, Fiorentini and Sansò (2019) analysed the function of tra parentesi ("( )") in presentday Italian, based on the ItTenTen corpus, and suggested that tra parentesi experienced a functional transformation from digressing markers to turn shifting mostly for politeness reasons.
The advent of the internet age has also derived more innovative uses of tildes. However, to our knowledge, research on innovative uses of tildes remains scarce. Lu et al. (2008: 185-186) in their book referred to the innovative uses of tildes on Chinese social media applications (e.g., QQ) in the following example (3). The authors interpreted the tilde ("∼") as a symbol of sound extension to enhance a certain emotional effect in that, from the perspective of physics, sounds have amplitudes and they are shaped like "∼". The number of tildes represented the extent to which the sound was elongated. In their opinion, originally, people have often used the extension of voice to express certain emotions in oral communication, such as surprise, dislike, etc., while in network verbal communication, the sound has been transformed into a visible symbol to enhance the communicative effects in online communication.
"yīngér" (wǎng míng A) duì "měi nǚ dōu shì hú lí jīng" (wǎng míng B) shuō: "āi yā ∼ ∼ liǎo bù qǐ a ∼ zài nǎ er chī de a ∼" "Username A said to Username B, "Dear me ∼ ∼ Great ∼ Where did you have lunch ∼" To briefly summarize the discussion so far, previous research has focused on the pragmatic, social, and interpersonal meanings conveyed by the innovative uses of ellipse (Baron and Ling 2011;Busch 2021;Hancock 2004;Ong 2011;Vandergriff 2013), exclamation marks (Hancock et al. 2007;Waseleski 2006), and periods (Androutsopoulos and Busch 2021; Gunraj et al. 2016;Houghton et al. 2018) etc., while research related to innovative tildes, the popular punctuation on Chinese social media, is still scarce and unsystematic. It is noteworthy that prior works on the innovative uses of sentence-final punctuation marks (e.g., periods, exclamation marks, and ellipses) could not clearly distinguish the traditional uses from the innovative uses of sentence-final punctuation, in that the two uses share the same place or distribution in naturally occurring messages. In this regard, the tilde's separation of uses through different places or distributions allows us to discern if tildes are employed innovatively or standardly.
Digital tildes ("∼") may convey more In light of this, the current research adopts quantitative and qualitative approaches to investigate the tildes on WeChat, a popular Chinese social media platform, thus expanding the research on the innovative uses of DP. Three research questions are addressed in the study: (1) What types of speech acts are performed in the messages with sentence-final tildes? (2) What functions do the innovative tildes perform on WeChat?
(3) Why do Chinese WeChat users resort to innovative tildes to perform these functions on WeChat?

Methodology
This section outlines the methodology employed in this study, which includes quantitative and qualitative analysis. It explains how the data was collected, coded, and analysed.

Why WeChat?
The current study was based on naturally occurring Chinese WeChat messages.
WeChat is a Chinese social media application launched by Tencent company in 2011 that allows users to send texts, audio, videos, photographs, locations, music, and files via messaging, as well as make voice and video calls. Two reasons contributed to the selection of this application for the study. Firstly, WeChat is the most widely used social media application in China. According to official figures published on the WeChat website in the third quarter of 2021, the platform has over 1.26 billion monthly active users. 2 WeChat is gradually becoming an important tool for understanding how Chinese users construct messages and interact online in innovative ways (Sandel et al. 2019). Secondly, WeChat is the only app in China that allows users to search for punctuation in messages, which is not available on other well-known apps, such as QQ and Weibo.

Data collection
Twelve WeChat users were randomly selected (6 males and 6 females; aged 20-30; mean age = 24.58, SD = 2.50) and volunteered to participate in our study. They are university students and Chinese native speakers. They were asked to search their chat records on WeChat's search box by inputting "∼". Then, they handed over the screenshots of WeChat chatting records involving tildes in person-to-person chatting (except group chatting and moment records) from June 1st to November 30th, 2020. Concerning ethics and privacy, all information that might be used to identify users, such as names, nicknames, profile photos, etc., was removed, as shown in Figure 1. A total of 548 messages containing tildes were collected, and five messages with traditional uses of tildes (percent: 0.91 %) were deleted based on their distribution, while 543 messages with sentence-final tildes (percent: 99.09 %) were the basis for data analysis. The observation that innovative tildes are used more frequently than traditional tildes in online communication justified the focus on innovative uses of tildes in our study.

Coding
This section evaluates the recurrent patterns and different uses of tildes collected from WeChat. 3 Since the innovative uses of tildes are sentence-final, it is important 3 This study focused on the simple innovative use of tildes and did not concern the combined uses of punctuation (e.g., ∼∼∼!!!) for two reasons: (1) The combined uses of punctuation in our data were scarce (only 5); (2) Given that previous studies on innovative tildes have been limited, we would like to have a systematic investigation of simple innovative tildes in the current study first, then the combined uses of punctuation will be explored in future studies.
Digital tildes ("∼") may convey more to clarify what kind of illocutionary forces were performed by messages. Hence, the classic framework of speech acts- Searle's (1969) taxonomy of speech acts, i.e., representatives, directives, commissives, expressives, and declaratives-was employed to code the messages with sentence-final tildes. It is noteworthy that Searle's taxonomy of speech acts is a general coding framework, and the final classification of innovative uses of tildes may be modified and adjusted with the data. All data were categorized and calculated with frequency. To ensure the objectivity of the coding results, a preliminary evaluation of 20 % of the data was conducted by the author and two colleagues who were blind to the purpose of this research. The result shows 95 % consistency, and the 5 % of inconsistent data was discussed further to unify the assessing standards.

Follow-up interview
Interview methods emphasize understanding people from their points of view (Williamson et al. 2002) and allow the researcher to gather a large amount of rich narrative data from a smaller subset of the population and to learn about topics that he or she might not have much knowledge of yet (Klofstad 2005). To deepen the understanding of innovative tilde uses in online communication, twelve tilde users on WeChat (6 males and 6 females) were selected and interviewed to objectively obtain the functions of and the reason for innovative tilde use. In faceto-face interviews, two main questions were discussed as follows. The interviewees were asked to answer the questions in Chinese. We encouraged interviewees to express themselves fully and did not interrupt them except for necessary statements and cues for questions. The interviews with the 12 participants lasted approximately 80 minutes in total, with some speaking eloquently and others just getting to the point. Finally, the audio recordings were turned into texts.

Findings
This section is a combination of quantitative and qualitative results of innovative tilde uses on WeChat, displaying their frequencies and percentages and illustrating the findings adhered to by the two main questions in the interview. After coding all data, we found that the sentence-final tildes in messages also co-occurred with onomatopoeia and vocatives to imitate sounds, which is transparently different from informative speech acts. As a result, the innovative tildes were overall separated into two categories: sounds and speech acts. The former involves two kinds of messages: onomatopoeia and vocatives, while the latter includes four types of speech acts, i.e., representatives, directives, expressives, and commissives. The reason for the absence of declaratives might be that person-to-person online communication is too informal to perform such illocutionary force. Table 1 shows the categories, subcategories, frequency counts, and percentages of innovative tilde uses analysed from 543 collected WeChat messages.
As observed in Table 1, innovative tildes were predominantly used for performing speech acts (89.32 %) rather than implying sounds (10.68 %). For sounds implied by tildes, onomatopoeia accounts for 3.13 %, while vocatives account for 7.55 %. The tildes in performing speech acts were more often used in expressives (41.07 %) and directives (24.31 %) than representatives (15.84 %) and commissives (8.10 %). The following subsections analyse each type of message co-occurring with tildes in more detail. The data may employ multiple sentence-final tildes (e.g., Beep∼∼∼∼∼), we only list one tilde in examples for convenience.

Innovative uses of tildes
In this example, "beep" and "boohoo" are onomatopoeia and the tildes following onomatopoeia seem to visualize sound waves and make messages vivid and  Table 1, expressives were the most frequently used in innovative uses, accounting for 41.07 % of all tilde uses. Expressive speech acts convey a psychological attitude or state in the speaker, including apologizing, blaming, congratulating, praising, etc. (Huang 2007: 107). In verbal communication, genuine and sincere emotive utterances are commonly accompanied by paralinguistic information, i.e., facial expressions or gestures, to create fully successful communicative effects, otherwise, the utterances are perceived to be insincere and mocking. As such, the innovative tilde aids in emotion enhancement in digital communication.

Directives
(7) 你可以帮我一个忙吗 ∼/快点起床 ∼ nǐ kě yǐ bāng wǒ yí gè máng ma ∼/kuài diǎn qǐ chuáng ∼ Can you do me a favor ∼/Get up now ∼ Directives were the second most frequently used in innovative uses, accounting for 24.31 % of all tilde uses. Directive speech acts, such as making requests, advice, and orders, convey the speaker's desire or wish for the addressee to do something (Huang 2007: 107). The directives are intrinsically impolite and threaten listeners' faces in online communication. Therefore, the innovative tildes are in lieu of the sentence-final question marks and exclamation marks in directives to lessen the abruptness and impoliteness. For example, in the above two examples, users make a request and an order respectively. If the bare request messages are sent, the receiver might feel offended or impolite and then reject the request and order directly or indirectly, especially when the senders and receivers are not close and unfamiliar. However, the tildes following directives seem to function as hedges to mitigate the face-threatening and impolite information and show friendliness to receivers, almost like adding a "please" or a smiling face to a direct request and order. In this sense, the requests and orders could probably be successfully achieved. Compared to expressives and directives, representatives (15.84 %) and commissives (8.10 %) less often co-occur with innovative tildes. Representatives including asserting, claiming, concluding, reporting, and stating, refer to the speaker representing the world as he or she believes it is, thus making the words fit the world of belief. Commissives refer to the speech act that commits the speaker to some future course of action and expresses the speaker's intention to do something (Huang 2007: 106-107). Both representatives and commissives usually end with periods that are frequently absent in online communication for convenience. Those neutral and serious texts are insufficient to communicate attitudes and emotions, and the sentence-final tildes have seemingly become a useful tool to ensure their correct interpretation, e.g., expressing speakers' positive, relaxing, sincere, and friendly tones.

Functions of the innovative tildes
Whereas the abovementioned innovative tildes imply sounds and perform four kinds of speech acts, they primarily serve three functions: (1) Sound extension. When tildes co-occur with onomatopoeia and vocatives, they are a kind of typographic resource for the vocal connotation of texts and function as sound extensions to compensate for the loss of audio information in online communication. The sentence-final tildes for implying sounds are Digital tildes ("∼") may convey more oriented towards communicating friendly tones and a faithful reproduction of how lasting the sound would have been if messengers made it in face-to-face contexts in the same way English messengers elongate words like "It's sooooooo (so) hot". As a matter of fact, the sound extension of innovative tildes echoes prior offline writings; for example, in Ye Shengtao's novella Night published in 1927, the tildes after the onomatopoeia "哇∼ ∼" (Boohoo∼ ∼) imitated a little boy's persistent cries.
(2) Pragmatic function. When the sentence-final tildes perform different speech acts, they will extend beyond the traditional function to convey pragmatic function and express social and interpersonal meaning. Similar to the function of emojis (Sampietro 2019), sentence-final tildes may be used as upgraders or downgraders to adjust the illocutionary forces of messages. Upgraders will increase the illocutionary power of speech acts, while downgraders will have the opposite effect. Specifically, when the tildes are in directives that might inherently damage addressees' faces, they are viewed as downgraders to soften the illocutionary power and to mitigate or reduce the face threats of messages, while when the tildes are used in emotional expressives (positive emotion in particular) such as congratulations and thanks, or rather neutral representatives and commissives, they will be upgraders to exacerbate and sharpen the positive emotional effects of those speech acts. (3) Entertaining function. When connoting typed texts on the keyboard, it is purposely playful in chatting to have the possibilities of intentional variations in orthography (e.g., visual dialect), strategic use of capitalization, lexical substitutions (metalinguistic cues of paraverbal quality, for example, to type "hmmmmm"), grammatical markers (e.g., reiterative use of exclamations), and iconic compositions of characters (emoticons) (Yus 2011: 163-164). Similarly, whether the sentence-final tildes are used for implying sounds or performing speech acts, they break the rules of formal typography to make messages informal, vivid, joyful, and interesting, which is meant to convey an entertaining or playful function.
Meanwhile, we triangulated the above statistical results and analysis based on responses from our interviews with some tilde users. Since the interviews were semi-structured, interviewees were encouraged to express their opinions freely. Firstly, when asked what types of speech acts were usually performed by tildes, the interviewees indicated the tildes were frequently used in sentences expressing emotions (e.g., joy, thanking, etc.) and conveying requesting, ordering, and asking, while sometimes the tildes were also used to state facts. Meanwhile, they added that some openings in messages (e.g., vocatives) and onomatopoeia involved sentencefinal tildes. Then, the interviewees had their own opinions on the functions of sentence-final tildes, such as to soften the directness of messages, demonstrate friendliness, defuse awkwardness, narrow the distance between speakers, and make fun. For example, a frequent tilde user (S3) stated, "When I saw my pals using tilde, I used it naturally. The tildes are so cute that make messages lovely and convey to receivers an air of friendliness and politeness". To conclude, the innovative tildes are used for implying sounds and performing speech acts by WeChat users in online communication, and the latter is more predominant than the former in overall innovative tilde uses. Meanwhile, the sentencefinal tildes could convey sound extension, pragmatic function, and entertaining function.

Discussion
In the previous section, we analysed different innovative uses and functions of tildes in WeChat messages supported by the interview data. The main finding is that innovative tildes are frequently used in speech acts (expressives and directives in particular) to convey pragmatic functions, i.e., enhancing or mitigating the illocutionary forces of speech acts, in online communication. In this part, we will discuss the pragmaticalization of innovative tildes and the reasons for pragmaticalized tildes.
Discursive creativity in new media is often poetic, usually playful, and always pragmatic (Thurlow 2012: 170). The innovative uses of tildes in online communication demonstrate the pragmaticalization of DP, which refers to the transformation from pure grammatical markers to pragmatic markers (cf. "to convey implicit social and pragmatic meaning', Androutsopoulos 2018; Androutsopoulos and Busch 2021). As the literature demonstrates, the sentence-final periods could be used to convey abruptness and insincerity (Gunraj et al. 2016;Houghton et al. 2018); the ellipses become the stance indicator of irony (Hancock 2004) and polite disagreement (Vandergriff 2013); and the exclamation marks redefine the function of friendliness (Waseleski 2006). The pragmaticalized innovative tildes, in line with other innovative punctuation, have recently become positive stance indicators indexing interpersonal and social meaning, i.e., to enhance the emotional effects of neutral or positive context or to reduce the potential face-threatening context. In this sense, pragmaticalized punctuation serves the same purpose as emoticons and emojis in digital communication, e.g., signaling the illocutionary force of the utterance (Dresner and Herring 2010), mitigating threatening formulations (Wilson 1993), eliminating indifference (Cao and Jin 2016), and enhancing informality (Yang and Liu 2021). Digital tildes ("∼") may convey more As a whole, it has been roughly concluded that DP has undergone two stages. Since the late 1980s, DP has deviated from the norms in offline texts through changes in form, such as repetition for emphasis or omission for typing shortcuts (Bieswanger 2013: 476;Busch 2021: 2;Jonsson 2019: 227). This kind of deviation retains the inherent syntactic functions of punctuation and is explicit enough to recognize the intended meaning encoded by senders. By the mid-2000s, DP kept the forms unchanged but redefined and repurposed their innovative uses to express pragmatic meanings subtly and implicitly, which require receivers to make inferences based on contextual information. It is evident that the innovative tildes in our study belong to the second stage of DP development.
Then, why have the sentence-final tildes been pragmaticalized into positive emotional markers? From the perspective of semiotics, the innovative tildes in online communication were interpreted as a symbol of sound extension to enhance a certain emotional effect (Lu et al. 2008: 185). According to some interviewees, the wave-like tildes visually seemed like the ups and downs of tones or a slight lift in the voice in the same way that "撒娇" (pronounced as sajiao) was realized. Sajiao is defined as a behavior to incite tenderness by deliberately acting like a spoiled child in front of someone (Qiu 2013), and this kind of culture is prevalent in East Asian countries (e.g., China, Japan, and Korea). In acoustic terms, sajiao can be realized as sentence-final rising intonation, stretched intonation or elongated tone, childlike articulation, etc. (Hardeman 2013: 45/51). When used appropriately, sajiao can shorten the interlocutors' social distance (Yueh 2017), index the social meaning of cuteness (Gao 2020), contribute to rapport management in the online context (Yang 2022), and serve as a polite negotiating strategy in disagreements (Wang et al. 2022). In our study, adding sentence-final tildes in messages is more like a Sajiao behavior through deliberately elongating sentence-final tones, to some extent. As a result, there is no doubt that innovative tildes have been accepted by Chinese messengers and have been regarded as a kind of positive stance indicator to actively adjust the illocutionary forces of speech acts and to represent cuteness, gentleness, friendliness, playfulness, etc., as opposed to abruptness or directness, in online communication.
Moreover, from the perspective of communicative principles, politeness, as a universal communicative strategy (Brown and Levinson 1987), aims to maintain human relationships both in real and virtual communication. Since online communication often takes place in a cue-filtered environment and lacks nonverbal communication, with fewer options and resources for contextualization (Lu et al. 2008: 188;Xie and Yus 2018), such as tones of voice and gestures (Houghton et al. 2018), it is necessary to add emotional and voice cues to messages so as to convey politeness in digital interaction. The innovative tildes, as positive stance indicators, compensate for the absence of extra-linguistic cues and have also been realized as politeness markers to maintain rapport and achieve successful online communication. The politeness motivation for tilde users echoes prior research on innovative punctuation in messages. The point case is the turn-medial ellipsis that is employed to mitigate the impact of negatively connoting acts (e.g., disagreements) by delaying or avoiding the dispreferred response (Baron and Ling 2011;Busch 2021;Ong 2011). Meanwhile, it is mostly for politeness reasons that tra parentesi ("( )") in present-day Italian experienced a functional transformation from digressing markers to turn shifting (Fiorentini and Sansò 2019).

Conclusions
The present study examined the innovative uses of tildes on WeChat, in which 543 messages with sentence-final tildes in person-to-person chatting were analysed, followed by interviews with 12 people. It has been found that a) the innovative tildes are frequently used in messages performing speech acts and rarely used in messages implying sounds; b) the innovative tildes perform sound extension, pragmatic function, and entertaining function; c) the innovative tildes are pragmalicalized due to the semiotic features of themselves and the politeness motivation of messengers for maintaining rapport management and achieving successful online communication.
The results of the present study have theoretical significance, for they contribute to a further understanding of the innovation of punctuation on Chinese social media, enriching the research on innovative non-verbal signals in digital discourse. Meanwhile, we hope that our study might have an application to chatting online so as to guide people to achieve more efficient and cooperative interpersonal communication. The findings of this article motivate us to investigate other innovative punctuation marks, such as repeated Chinese full stops ("。。。"), left parenthesis ("(") in digital interaction, the combined uses of punctuation (e.g., "∼∼∼!!!"), and innovative use of DP in triadic or multi-party contexts, such as group chatting.
Research funding: This work was supported by the Fundamental Research Funds for the Central Universities under Grant number 2022JX012. Digital tildes ("∼") may convey more