A Myriad of Ways to Say: “Wear a mask!” (2022)

Abstract: This paper presents a small corpus of notices displayed at entrances of various Belgrade public premises asking those who enter to wear a mask. We analyze the various aspects of these notices: their physical appearance, script, lexica, syntax and style. A special attention is paid to various obligatory and optional parts of these notices. Obligatory parts deal with wearing masks, keeping the distance, limiting the number of persons on premises and using disinfection. We developed local grammars for modelling phrases that require wearing masks, that can be used both for recognition and for generation of paraphrases.

## introduction short messages have been attracting attention of linguists and researchers in natural language processing (nlp) for some time. one of the reasons is that it is a widespread type of communication, and is not limited to use among young people and entertainment. it has been noticed that short messages use a specific language and a particular style. for that reason, numerous corpora of short messages have been collected and can be explored by means of nlp tools. a corpus of 88,000 french sms messages was collected, anonymized and made available for research purposes @xcite . @xcite presented a large twitter corpus of 97 million posts and made it publicly available for researchers working in social media, nlp and large-scale data processing. 1 in many cases researchers tailored their own corpora of short messages suiting their purposes. @xcite compiled a corpus of 864 1 the corpus is no longer available due to change in twitter policy. sms messages produced by french-speaking adolescents in order to analyze the effects of writers' characteristics on message length, dialogue structure, and message function. a corpus of french twitter posts containing complaints regarding railway services was used to investigate linguistic directness and indirectness and differentiate them from perceived (im)politeness @xcite . graffiti on the walls of urban spaces are also a type of short messages; moreover, they have a much longer history than messages on today's social media. they have been analyzed from various perspectives: political, sociocultural, and linguistic @xcite . the graffiti for analysis are often selected from a specific area, such as a university campus. authors applied corpus method to analyse 378 graffiti found on walls of two jordan universities @xcite , and found that they express different themes: personal, social, national, religious, political etc. a formulaic short messages are often sent on the occasion of christmas and new year. christmas and new year messages issued by important persons, like heads of state, which are far from being formulaic, have received more than their fair share of attention @xcite . still, some researchers were interested in the formulaic expressions @xcite analysed how the language of chinese sms messages conveying christmas wishes reflects a shift in cultural values and customs, while włosowicz (2011) analysed how foreign language learners' mother tongue and cultural background influence their birthday, christmas and new year's wishes. linguists showed interest in short messages written in serbian as well. the use of shortening, clipping and elliptic constructions in text messages was analysed by several authors @xcite . graffiti that emerged in serbia in its transition era were analysed and messages were classified in overarching categories, as hate messages and love messages @xcite . nlp specialists collected corpora of various types of short messages in order to solve different problems. @xcite prepared a corpus of 5,500 serbian sms messages to test the system for detecting their sender. a corpus of 9,059 serbian twitter posts was collected in order to determine how their sentiment is affected by the use of negation @xcite . @xcite collected and manually annotated for hate-speech 6,436 tweets to be used for training hate-speech detection applications. in this paper we are interested in notices that announce precaution measures related to the covid-19 pandemic at front doors of public premises. these notices are similar to graffiti as they are public and are not a product of social media. however, contrary to graffiti, their content is restricted and in that respect they are closer to christmas and new year wishes. our paper is organized as follows. section 2 presents a small corpus of notices related to precaution measures against covid-19 virus. in section 3 the lexica used in these notices is analysed. sections that follow are restricted to the part of these notices that concern protective masks: their basic syntactic patterns (section 4) and their semantic value (while in section 5). finally in section 6 we show by generating mask messages of determined structures that there are myriad ways to say: "wear a mask!". in section 7 we discuss avenues for future research. ## about the corpus our corpus is based on notices that were photographed between 21 january 2021 and 30 march 2022 and then re-typed. we considered as a single notice everything written on one sheet of paper. not all notices were originally composed; instead, many were acquired from internet and other sources, and used on entrances to many different facilities. we filtered only different notices from all notices photographed. we do not claim that our set of notices is in any way representative since all notices were photographed in the center of belgrade at the walking distance from the place of the residence of the authors of this paper. the total number of photographed notices is 231. physical appearance -the majority of notices were printed on a paper (207), 23 notices were handwritten. there was one 3d notice -a word "obavezno" (obligatory) written on an actual mask. capitalization -the majority of notices (165) were written using only upper-case letters, 45 notices were written using lower-case letters, while in 21 notices only some parts were written using only upper-case letters for emphasis. script -the majority of notices(187) were written using latin script. among them 18 did not use diacritics. 44 (19%) of notices were written in cyrillic script. among 23 handwritten notices, 8 (34.7%) were written in cyrillic. these findings are in line with the conclusions reached by @xcite that the latin alphabet dominates over cyrillic on serbian news websites and the use of non-standard latin orthographic variants (diacritics omission) is becoming stable. emphasizing -various methods of emphasis were used. many notices included images (of a mask, people maintaining a distance, etc.) -68 (29.4%) such notices were in the selected set. other means of emphasizing were: using bold font (18), underlining (23), colors (mostly red) (29), increasing the font size (13). in many cases more than one mean of emphasizing was used. the other means of emphasizing the message of the notice was the use of the exclamation mark. it was used in 52 notices, either only once (40) or repeatedly (two times, three times, and up to 16 times). it is interesting to note that only once an emoticon was used (a smiley). multilinguality -all notices were written in serbian. however, some of them had translations in english, and they vary in form as much as those written in serbian that we will explore in following sections. these 5 notices in english concerning the use of masks were: "please wear protective mask in public areas", "no entry without face mask", "use a protective mask", "face mask required", "please don't enter without a face mask". in some notices images were intertwined with words to convey the meaning. for instance, <img of a @xmath0. such notices were excluded form further analysis, as well as notices or their parts written in english. the length of notices is between one word (a word "obavezno" (obligatory) written on an actual mask) and 84 words. the average length of notices is 14.3 words, while two thirds of them were proceedings of clib 2022 written using no more than 15 words. ## lexica used in notices when preparing our tiny little corpus the notices were typed as they were and corrected only evident typos, leaving grammatical and orthographic errors. the corpus consists of 3,581 tokens and 3,285 words. among words, there were 193 different nouns, 49 different verbs, 57 different adjectives and 15 different adverbs. the five most frequently used nouns, verbs, adjectives and nouns are listed in in our sample specific groups of nouns were identified. the first group containing 34 nouns were used to refer to places to which notices about protective measures apply. here one can distinguish the most general concepts: objekat (facility) (39), prostor (space, area) (13), prostorija (room) (9), zgrada (building) (2), mesto (place) (1). these concepts can be further qualified: prodajni prostor (shopping area), poslovni prostor (business area), javni prostor (public area), zatvoreni prostor (enclosed area) prodajni objekat (shopping facility), maloprodajni objekat (retail shopping facility), radna prostorija (working space), javno mesto (public place). the more specific concept was represented by three nearly synonymous words radnja (32) prodavnica (12) (shop), maloprodaja (retail) (1). the remaining 26 nouns were used to name a place for a specific activity, like menjačnica (exchange office), pekara (bakery), fakultet (faculty). the other group of specific nouns refers to people to whom notices are addressed. here also very general concepts were used, lexicalized by osoba (39) and lice (8) (person), gradjanin (1) (citizen), ljudi (people) (4). besides them, more specific concepts were used for potential: kupac (shopper) (28), potrošač (consumer) (14), mušterija (customer) (3), while other concepts were specific to particular activity, like gost (guest) (1) and posetilac (visitor) (7). it should be noted that concepts referred to by these two specific groups of nouns are related in proceedings of clib 2022 a specific way. osoba and lice (person) are applicable to all types of premises, while visitors of biblioteka (library) and sala (hall) cannot be designated as kupac, potrošač or mušterija. moreover, even though mušterija, kupac and potrošač can all be translated as 'customer', only mušterija is applicable to menjačnica (exchange office) and frizerski salon (hairdresser), while kupac and potrošač are not. on the other hand, the library patrons are customarily designated as posetilac (visitor) or član (member), while mušterija cannot be used. the larger and more versatile corpus is needed to fully investigate relations between designations for types of visitors and types of venues. finally, even in this small corpus we have ambiguity: lice can mean both face and person. in the former meaning it was used 9 times, e.g. maska za lice (face mask), while in the later case it was used 8 times. ## the analysis of mask messages in this section we will present basic syntactic patterns of one section of selected notices, namely the one related to wearing masks. there were 207 such statements, with a total of 1,466 tokens, and 1,365 words. the most frequent of 72 different nouns is maska (204), followed by nošenje (wearing) (91) and ulazak (entering) (37). the most frequent of 22 different verbs is moliti (to request) (29), followed by nositi (to wear) (25) and staviti (to put) (10). the most frequent of 21 different adjectives is obavezan (mandatory) (124), zaštitni (protective) (83) and zatvoren (enclosed) (8). in total, 8 different adverbs have been identified, of which only 2 occured more than once: obavezno (mandatorily) (14) and isključivo (exclusively) (2). the most frequent noun maska is often characterized as zaštitna maska (protective mask), higijenska maska (hygienic mask) and maska za lice (face mask), and can be additionally described as ličan (personal). in the descriptions bellow [maska] stands for all these possibilities. also, in this context korišćenje and upotreba (usage) are treated as synonyms for nošenje ([korišćenje]); similarly, synonym of nositi (to wear) is koristiti (to use), while staviti (to put) is also used in a similar context ([koristiti]). as for their syntactic patterns, the majority of mask messages has one of 9 general forms discussed below. their basic syntactic patterns were analyzed using the udpipe @xcite and they are presented in figures 1-3. 3 all these basic sentences can be modified with additional phrases: molimo vas... for the recognition of these basic patterns with their various realizations we developed within unitex/gramlab foot_2 local grammars that are supported by serbian morphological dictionaries @xcite . ## hidden messages and sentiment values although the parts of notices related to mask wearing are very short, less than 7 words on average, some of them convey additional meaning to the main one, which is that one is requested to wear a mask. for instance, in two cases the statement contained obavezno nošenje maski preko nosa i usta (mandatory to wear a mask over the nose and mouth) meaning that it is not enough to wear a mask, but also to wear it properly. moreover, if notice said ulaz u objakt s maskom (entry in the facility (allowed only) with a mask), it would be possible to interpret it as if one was required to wear a mask only while entering the facility, but not throughout the visit. therefore, some notices added explicit clarification: nije dozvoljen ulazak odnosno boravak lica bez ličnih zaštitnih maski (it is not allowed for persons to enter or stay without personal protective masks). the tone of messages related to masks vary across our corpus, and goes from very polite to severe or even unpleasant. notes starting with molimo da... or hvala vam što... always have a positive tone. however, some expressions like zabranjeno je... (it is forbidden...) are never used with "please", and cases like that were not found in our set. also, a neutral expression like nošenje maske je obavezno (wearing a mask is obligatory) can be made more severe by adding bez izuzetka (without exceptions) or similar. the level of severity of mask notices according to their lexica and syntax can be ranked in the following way strating from those most strict: there is a serbian proverb lepa reč gvozdena vrata otvara (a nice word opens an iron gate). in this case, we cannot say which announcements, polite or strict, appealed to people more to respect the measures. ## generating mask messages we used the local grammars developed for the recognition of 9 basic patterns with their various realizations that were systematized on the basis of data found in our corpus to generate possible mask messages within unitex. in order to avoid an excessive number of possibilities, synonyms retrieved in our set, sometimes also hiponyms and hiperonyms, designating concepts maska, kupac/osoba, objekat/radnja, ulazak were not used for generation. by doing so we obtained: type 1 -19,520 messages, for example: u ovoj prostoriji maska preko nosa i usta je obavezna (in this room a mask over a nose and a mouth is obligatory); type 2 -10,944 messages, for example: upotreba maski na licu u ovom objektu je obavezna (the use of masks over the face in this facility is obligatory); type 3 -110,784 messages, for example: molimo, stavite masku preko nosa i usta obavezno ako ulazite u ovu radnju (please, put a mask over your nose and mouth obligatorily if you enter this shop); type 4 -62,160 messages, for example: molimo da imate vašu masku na licu pri ulasku i za vreme boravka u ovoj prostoriji (we ask you to have your mask on (your) face when entering and during (your) stay in this room); type 5 -14,240 messages, for example: u objektu obavezno morate nositi masku (in the facility you mast be sure to wear a mask); type 6 -35,328 messages, for example: mole se svi kupci da prilikom ulaska u ovu radnju obavezno stave masku (all customers are asked to be sure to put a mask when entering this shop); type 7 -6,544 messages, for example: ulazak nije dozvoljen osobama bez maske (entering is not allowed to persons without a mask); type 8 -11,520 messages, for example: dozvoljen je ulazak isključivo osobama sa maskom na licu (only persons with a mask on (their) face are allowed to enter); type 9 -19,710 messages, for example mole se kupci da ne ulaze u ovaj objekat bez maske (the customers are asked not to enter this facility without a mask). in a total, we produced 290,750 ready to use, correct messages all conveying the same basic meaning: "wear a mask". ## conclusion in this paper we presented the analysis of a set of notices collected from front doors of various premises that require compliance with protective measures against covid-19. we analysed lexica and syntactic patterns of mask notices in more detail which enabled us to generate notices featuring one of their basic structures. our next step will be the production of paraphrased sentences with a full morphosyntactic description. besides that we will analyse in the similar way messages about other covid-19 protective measures. moreover, we will collect other public announcements that emerge spontaneously and convey the similar meaning, like zatvarajte vrata za sobom (close the door behind you) or ne primamo reklame (we do not accept advertisements). the goal of out future project is to produce a big and versatile set of paraphrases.