Vietnamese language

Vietnamese (Vietnamese: tiếng Việt) is an Austroasiatic language that originated in Vietnam, where it is the national and official language. Vietnamese is spoken natively by over 70 million people, several times as many as the rest of the Austroasiatic family combined.[4] It is the native language of the Vietnamese (Kinh) people, as well as a second language or first language for other ethnic groups in Vietnam. As a result of emigration, Vietnamese speakers are also found in other parts of Southeast Asia, East Asia, North America, Europe, and Australia. Vietnamese has also been officially recognized as a minority language in the Czech Republic.[a]

Like many other languages in Southeast Asia and East Asia, Vietnamese is an analytic language with phonemic tone. It has head-initial directionality, with subject–verb–object order and modifiers following the words they modify. It also uses noun classifiers. Its vocabulary has had significant influence from Chinese and French.

Vietnamese was historically written using Chữ Nôm, a logographic script using Chinese characters to represent Sino-Vietnamese vocabulary and some native Vietnamese words, together with many locally-invented characters to represent other words.[5][6] French colonial rule of Vietnam led to the official adoption of the Vietnamese alphabet (Chữ Quốc ngữ) which is based on Latin script. It uses digraphs and diacritics to mark tones and some phonemes. Chữ Nôm fell out of use in Vietnam by the early 20th century.

Early linguistic work some 150 years ago[7] classified Vietnamese as belonging to the Mon–Khmer branch of the Austroasiatic language family (which also includes the Khmer language spoken in Cambodia, as well as various smaller and/or regional languages, such as the Munda and Khasi languages spoken in eastern India, and others in Laos, southern China and parts of Thailand). Later, Muong was found to be more closely related to Vietnamese than other Mon–Khmer languages, and a Viet–Muong subgrouping was established, also including Thavung, Chut, Cuoi, etc.[8] The term "Vietic" was proposed by Hayes (1992),[9] who proposed to redefine Viet–Muong as referring to a subbranch of Vietic containing only Vietnamese and Muong. The term "Vietic" is used, among others, by Gérard Diffloth, with a slightly different proposal on subclassification, within which the term "Viet–Muong" refers to a lower subgrouping (within an eastern Vietic branch) consisting of Vietnamese dialects, Muong dialects, and Nguồn (of Quảng Bình Province).[10]

Vietnamese belongs to the Northern (Viet–Muong) clusters of the Vietic branch, spoken by the Vietic peoples.

In the distant past, Vietnamese shared more characteristics common to other languages in South East Asia and with the Austroasiatic family, such as an inflectional morphology and a richer set of consonant clusters, which have subsequently disappeared from the language under Chinese influence. Vietnamese is heavily influenced by its location in the Mainland Southeast Asia linguistic area, with the result that it has acquired or converged toward characteristics such as isolating morphology and phonemically distinctive tones, through processes of tonogenesis. These characteristics have become part of many of the genetically unrelated languages of Southeast Asia; for example, Tsat (a member of the Malayo-Polynesian group within Austronesian), and Vietnamese each developed tones as a phonemic feature. The ancestor of the Vietnamese language is usually believed to have been originally based in the area of the Red River Delta in what is now northern Vietnam.[11][12][13]

Distinctive tonal variations emerged during the subsequent expansion of the Vietnamese language and people into what is now central and southern Vietnam through conquest of the ancient nation of Champa and the Khmer people of the Mekong Delta in the vicinity of present-day Ho Chi Minh City, also known as Saigon.

Vietnamese was primarily influenced by Chinese, which came to predominate politically in the 2nd century BC. After Vietnam achieved independence in the 10th century, the ruling class adopted Classical Chinese as the formal medium of government, scholarship and literature. With the dominance of Chinese came radical importation of Chinese vocabulary and grammatical influence. A portion of the Vietnamese lexicon in all realms consists of Sino-Vietnamese words (They are about a third of the Vietnamese lexicon, and may account for as much as 60% of the vocabulary used in formal texts.[14])

When France invaded Vietnam in the late 19th century, French gradually replaced Chinese as the official language in education and government. Vietnamese adopted many French terms, such as đầm (dame, from madame), ga (train station, from gare), sơ mi (shirt, from chemise), and búp bê (doll, from poupée).

Henri Maspero described six periods of the Vietnamese language:[15][16]

The following diagram shows the phonology of Proto-Viet–Muong (the nearest ancestor of Vietnamese and the closely related Muong language), along with the outcomes in the modern language:[17][18][19][20]

^1 According to Ferlus, */tʃ/ and */ʄ/ are not accepted by all researchers. Ferlus 1992[17] also had additional phonemes */dʒ/ and */ɕ/.

^2 The fricatives indicated above in parentheses developed as allophones of stop consonants occurring between vowels (i.e. when a minor syllable occurred). These fricatives were not present in Proto-Viet–Muong, as indicated by their absence in Muong, but were evidently present in the later Proto-Vietnamese stage. Subsequent loss of the minor-syllable prefixes phonemicized the fricatives. Ferlus 1992[17] proposes that originally there were both voiced and voiceless fricatives, corresponding to original voiced or voiceless stops, but Ferlus 2009[18] appears to have abandoned that hypothesis, suggesting that stops were softened and voiced at approximately the same time, according to the following pattern:

^3 In Middle Vietnamese, the outcome of these sounds was written with a hooked b (ꞗ), representing a /β/ that was still distinct from v (then pronounced /w/). See below.

^4 It is unclear what this sound was. According to Ferlus 1992,[17] in the Archaic Vietnamese period (c. 10th century AD, when Sino-Vietnamese vocabulary was borrowed) it was *, distinct at that time from *r.

A large number of words were borrowed from Middle Chinese, forming part of the Sino-Vietnamese vocabulary. These caused the original introduction of the retroflex sounds /ʂ/ and /ʈ/ (modern s, tr) into the language.

Proto-Viet–Muong had no tones to speak of. The tones later developed in some of the daughter languages from distinctions in the initial and final consonants. Vietnamese tones developed as follows:

Glottal-ending syllables ended with a glottal stop /ʔ/, while fricative-ending syllables ended with /s/ or /h/. Both types of syllables could co-occur with a resonant (e.g. /m/ or /n/).

At some point, a tone split occurred, as in many other Southeast Asian languages. Essentially, an allophonic distinction developed in the tones, whereby the tones in syllables with voiced initials were pronounced differently from those with voiceless initials. (Approximately speaking, the voiced allotones were pronounced with additional breathy voice or creaky voice and with lowered pitch. The quality difference predominates in today's northern varieties, e.g. in Hanoi, while in the southern varieties the pitch difference predominates, as in Ho Chi Minh City.) Subsequent to this, the plain-voiced stops became voiceless and the allotones became new phonemic tones. Note that the implosive stops were unaffected, and in fact developed tonally as if they were unvoiced. (This behavior is common to all East Asian languages with implosive stops.)

As noted above, Proto-Viet–Muong had sesquisyllabic words with an initial minor syllable (in addition to, and independent of, initial clusters in the main syllable). When a minor syllable occurred, the main syllable's initial consonant was intervocalic and as a result suffered lenition, becoming a voiced fricative. The minor syllables were eventually lost, but not until the tone split had occurred. As a result, words in modern Vietnamese with voiced fricatives occur in all six tones, and the tonal register reflects the voicing of the minor-syllable prefix and not the voicing of the main-syllable stop in Proto-Viet–Muong that produced the fricative. For similar reasons, words beginning with /l/ and /ŋ/ occur in both registers. (Thompson 1976[20] reconstructed voiceless resonants to account for outcomes where resonants occur with a first-register tone, but this is no longer considered necessary, at least by Ferlus.)

Old Vietnamese/Ancient Vietnamese was a Vietic language which was separated from Viet–Muong around 9th century, and evolved to Middle Vietnamese by 16th century. The sources for the reconstruction of Old Vietnamese are Nom texts, such as the 12th-century/1486 Buddhist scripture Phật thuyết Đại báo phụ mẫu ân trọng kinh ("Sūtra explained by the Buddha on the Great Repayment of the Heavy Debt to Parents"),[22] old inscriptions, and late 13th-century (possibly 1293) glossary by Chinese diplomat Chen Fu (c. 1259 – 1309).[23] Old Vietnamese used Chinese characters phonetically where each word, monosyllabic in Modern Vietnamese, is written with two Chinese characters or in a composite character made of two different characters.[24]

For examples, the modern Vietnamese word "trời" (heaven) was read as *plời in Old/Ancient Vietnamese.

The writing system used for Vietnamese is based closely on the system developed by Alexandre de Rhodes for his 1651 Dictionarium Annamiticum Lusitanum et Latinum. It reflects the pronunciation of the Vietnamese of Hanoi at that time, a stage commonly termed Middle Vietnamese (tiếng Việt trung đại). The pronunciation of the "rime" of the syllable, i.e. all parts other than the initial consonant (optional /w/ glide, vowel nucleus, tone and final consonant), appears nearly identical between Middle Vietnamese and modern Hanoi pronunciation. On the other hand, the Middle Vietnamese pronunciation of the initial consonant differs greatly from all modern dialects, and in fact is significantly closer to the modern Saigon dialect than the modern Hanoi dialect.

The following diagram shows the orthography and pronunciation of Middle Vietnamese:

^1 [p] occurs only at the end of a syllable.
^2 This symbol, "Latin small letter B with flourish", looks like: ȸ. It has a rounded hook that starts halfway up the left side (where the top of the curved part of the b meets the vertical, straight part) and curves about 180 degrees counterclockwise, ending below the bottom-left corner.
^3 [j] does not occur at the beginning of a syllable, but can occur at the end of a syllable, where it is notated i or y (with the difference between the two often indicating differences in the quality or length of the preceding vowel), and after /ð/ and /β/, where it is notated ĕ. This ĕ, and the /j/ it notated, have disappeared from the modern language.

Note that b [ɓ] and p [p] never contrast in any position, suggesting that they are allophones.

The language also has three clusters at the beginning of syllables, which have since disappeared:

Most of the unusual correspondences between spelling and modern pronunciation are explained by Middle Vietnamese. Note in particular:

De Rhodes's orthography also made use of an apex diacritic, as in o᷄ and u᷄, to indicate a final labial-velar nasal /ŋ͡m/, an allophone of /ŋ/ that is peculiar to the Hanoi dialect to the present day. This diacritic is often mistaken for a tilde in modern reproductions of early Vietnamese writing.

As the national language, Vietnamese is the lingua franca in Vietnam. It is also spoken by the Gin traditionally residing on three islands (now joined to the mainland) off Dongxing in southern Guangxi Province, China.[25] A large number of Vietnamese speakers also reside in neighboring countries of Cambodia and Laos.

In the United States, Vietnamese is the fifth most spoken language, with over 1.5 million speakers, who are concentrated in a handful of states. It is the third most spoken language in Texas and Washington; fourth in Georgia, Louisiana, and Virginia; and fifth in Arkansas and California.[26] Vietnamese is the seventh most spoken language in Australia.[27] In France, it is the most spoken Asian language and the eighth most spoken immigrant language at home.[28]

Vietnamese is the sole official and national language of Vietnam. It is the first language of the majority of the Vietnamese population, as well as a first or second language for the country's ethnic minority groups.[29]

In the Czech Republic, Vietnamese has been recognized as one of 14 minority languages, on the basis of communities that have resided in the country either traditionally or on a long-term basis. This status grants the Vietnamese community in the country a representative on the Government Council for Nationalities, an advisory body of the Czech Government for matters of policy towards national minorities and their members. It also grants the community the right to use Vietnamese with public authorities and in courts anywhere in the country.[30][31]

Vietnamese is increasingly being taught in schools and institutions outside of Vietnam, a large part which is contributed by its large diaspora. In countries with strongly established Vietnamese-speaking communities such as the United States, France, Australia, Canada, Germany, and the Czech Republic, Vietnamese language education largely serves as a cultural role to link descendants of Vietnamese immigrants to their ancestral culture. Meanwhile, in countries near Vietnam such as Cambodia, Laos, and Thailand, the increased role of Vietnamese in foreign language education is largely due to the recent recovery of the Vietnamese economy.[32][33]

Since the 1980s, Vietnamese language schools (trường Việt ngữ/ trường ngôn ngữ Tiếng Việt) have been established for youth in many Vietnamese-speaking communities around the world, notably in the United States.[34][35]

Similarly, since the late 1980s, the Vietnamese-German community has enlisted the support of city governments to bring Vietnamese into high school curriculum for the purpose of teaching and reminding Vietnamese German students of their mother-tongue. Furthermore, there has also been a number of Germans studying Vietnamese due to increased economic investments and business.[36][37]

Historic and stronger trade and diplomatic relations with Vietnam and a growing interest among the French Vietnamese population (one of France's most established non-European ethnic groups) of their ancestral culture have also led to an increasing number of institutions in France, including universities, to offer formal courses in the language.[38]

Vietnamese has a large number of vowels. Below is a vowel diagram of Vietnamese from Hanoi (including centering diphthongs):

Front and central vowels (i, ê, e, ư, â, ơ, ă, a) are unrounded, whereas the back vowels (u, ô, o) are rounded. The vowels â [ə] and ă [a] are pronounced very short, much shorter than the other vowels. Thus, ơ and â are basically pronounced the same except that ơ [əː] is of normal length while â [ə] is short – the same applies to the vowels long a [aː] and short ă [a].[b]

The centering diphthongs are formed with only the three high vowels (i, ư, u). They are generally spelled as ia, ưa, ua when they end a word and are spelled iê, ươ, uô, respectively, when they are followed by a consonant.

In addition to single vowels (or monophthongs) and centering diphthongs, Vietnamese has closing diphthongs[c] and triphthongs. The closing diphthongs and triphthongs consist of a main vowel component followed by a shorter semivowel offglide /j/ or /w/.[d] There are restrictions on the high offglides: /j/ cannot occur after a front vowel (i, ê, e) nucleus and /w/ cannot occur after a back vowel (u, ô, o) nucleus.[e]

The correspondence between the orthography and pronunciation is complicated. For example, the offglide /j/ is usually written as i; however, it may also be represented with y. In addition, in the diphthongs [āj] and [āːj] the letters y and i also indicate the pronunciation of the main vowel: ay = ă + /j/, ai = a + /j/. Thus, "tay" "hand" is [tāj] while "tai" "ear" is [tāːj]. Similarly, u and o indicate different pronunciations of the main vowel: au = ă + /w/, ao = a + /w/. Thus, thau "brass" is [tʰāw] while thao "raw silk" is [tʰāːw].

The consonants that occur in Vietnamese are listed below in the Vietnamese orthography with the phonetic pronunciation to the right.

Some consonant sounds are written with only one letter (like "p"), other consonant sounds are written with a digraph (like "ph"), and others are written with more than one letter or digraph (the velar stop is written variously as "c", "k", or "q").

Not all dialects of Vietnamese have the same consonant in a given word (although all dialects use the same spelling in the written language). See the language variation section for further elaboration.

The analysis of syllable-final orthographic ch and nh in Vietnamese has had different analyses. One analysis has final ch, nh as being phonemes /c/, /ɲ/ contrasting with syllable-final t, c /t/, /k/ and n, ng /n/, /ŋ/ and identifies final ch with the syllable-initial ch /c/. The other analysis has final ch and nh as predictable allophonic variants of the velar phonemes /k/ and /ŋ/ that occur after the upper front vowels i /i/ and ê /e/; although they also occur after a, but in such cases are believed to have resulted from an earlier e /ɛ/ which diphthongized to ai (cf. ach from aic, anh from aing). (See Vietnamese phonology: Analysis of final ch, nh for further details.)

Pitch contours and duration of the six Northern Vietnamese tones as spoken by a male speaker (not from Hanoi). Fundamental frequency is plotted over time. From Nguyễn & Edmondson (1998).

Each Vietnamese syllable is pronounced with one of six inherent tones,[f] centered on the main vowel or group of vowels. Tones differ in:

Tone is indicated by diacritics written above or below the vowel (most of the tone diacritics appear above the vowel; however, the nặng tone dot diacritic goes below the vowel).[g] The six tones in the northern varieties (including Hanoi), with their self-referential Vietnamese names, are:

Other dialects of Vietnamese may have fewer tones (typically only five).

In Vietnamese poetry, tones are classed into two groups: (tone pattern)

Words with tones belonging to a particular tone group must occur in certain positions within the poetic verse.

Vietnamese Catholics practice a distinctive style of prayer recitation called đọc kinh, in which each tone is assigned a specific note or sequence of notes.

Vietnamese, like Chinese and many languages in Southeast Asia, is an analytic language. Vietnamese does not use morphological marking of case, gender, number or tense (and, as a result, has no finite/nonfinite distinction).[h] Also like other languages in the region, Vietnamese syntax conforms to subject–verb–object word order, is head-initial (displaying modified-modifier ordering), and has a noun classifier system. Additionally, it is pro-drop, wh-in-situ, and allows verb serialization.

Some Vietnamese sentences with English word glosses and translations are provided below.

"He/she/it only eats Vietnamese rice (or food, especially spoken by the elderly)."

Although Vietnamese roots are classified as Austroasiatic, Vietic and Viet-Muong, the result of language contact with Chinese heavily influenced the Vietnamese language, causing it to diverge from Viet-Muong into Vietnamese. For instance, the Vietnamese word quản lý, meaning management (noun) or manage (verb) is likely descended from the same word as guǎnlǐ (管理) in Chinese, kanri (管理, かんり) in Japanese, and gwanli (관리, 管理) in Korean. Besides English and French which have made some contributions to Vietnamese language, Japanese loanwords into Vietnamese are also a more recently studied phenomenon.

Modern linguists describe modern Vietnamese having lost many Proto-Austroasiatic phonological and morphological features that original Vietnamese had.[40] The Chinese influence on Vietnamese corresponds to various periods when Vietnam was under Chinese rule, and subsequent influence after Vietnam became independent. Early linguists thought that this meant Vietnamese lexicon then received only two layers of Chinese words, one stemming from the period under actual Chinese rule and a second layer from afterwards. These words are grouped together as Sino-Vietnamese vocabulary.

However, according to linguist John Phan, “Annamese Middle Chinese” was already used and spoken in the Red River Valley by the 1st century CE, and its vocabulary significantly fused with the co-existing Proto-Viet-Muong language, the immediate ancestor of Vietnamese. He lists three major classes of Sino-Vietnamese borrowings:[41][42][43] Early Sino-Vietnamese (Han Dynasty (ca. 1st century CE) and Jin Dynasty (ca. 4th century CE), Late Sino-Vietnamese (Tang Dynasty), Recent Sino-Vietnamese (Ming Dynasty and afterwards)

Additionally, the French presence in Vietnam from 1777 to the Geneva Accords of 1954 resulted in significant influence from French into eastern Mainland Southeast Asia (Laos, Cambodia, Vietnam ). 'Cà phê' in Vietnamese was derived from French café (coffee). Yogurt in Vietnamese is "sữa chua", but also calqued from French (yaourt) into Vietnamese (da ua - /j/a ua). Phô mai meaning cheese is also derived from French:fromage. Musical note was also borrowed into Vietnamese as "nốt or nốt nhạc" (musical notes)" from French (note de musique).

Some English words were incorporated into Vietnamese as loan words, such as "TV" borrowed as "tivi", but still officially called truyền hình. Some other borrowings are calques, translated into Viet, for example, 'software' is translated into 'phần mềm' (literally meaning "soft part"). Some scientific terms such as "biological cell" were derived from Chữ Hán, ( 细胞 - tế bào), whilst other scientific names such as "acetylcholine" are unaltered. Words like "peptide", may be seen as peptit.

Japanese loanwords are a more recently studied phenomenon, with a paper by Nguyen & Le (2020) classifying three layers of Japanese loanwords, where the third layer was used by Vietnamese who studied Japanese and the first two layers being the main layers of borrowings that were derived from Japanese.[44] The first layer consisted of Kanji words created by Japanese to represent Western concepts that were not readily available in Chinese or Japanese, where by the end of the 19th century they were imported to other Asian languages.[45] This first layer was called Sino-Vietnamese words of Japanese-origins. For example, the Vietnamese term for "association club", câu lạc bộ, which was borrowed from Chinese (俱乐部; Mandarin pinyin - jùlèbù; Cantonese jyutping - keoi1 lok6 bou6), which was borrowed from Japanese (kanji - 倶楽部; katakana - クラブ; rōmaji - kurabu) which came from English ("club"), resulting in indirect borrowing from Japanese.

The second layer was from brief Japanese occupation of Vietnam from 1940 until 1945. However, Japanese cultural influence in Vietnam started significantly from the 1980s. This new, second layer of Japan-origin loanwords is distinctive from Sino-Vietnamese words of Japanese-origin in that they were borrowed directly from Japanese. This vocabulary included words representative of Japanese culture, such as kimono, sumo, samurai, and bonsai from modified Hepburn romanisation. These loanwords are coined as "new Japanese loanwords". A significant number of new Japanese loanwords were also of Chinese origin. Sometimes, the same concept can be described using both Sino-Vietnamese words of Japanese origin (first layer) and new Japanese loanwords (second layer). For example, judo can be referred to as both judo and nhu đạo, the Vietnamese reading of 柔道.[44]

Other words, like muôn thuở meaning forever are seen to be purely Vietnamese invention, which used to be scribed Nôm characters, which were compounded Chinese characters, which are now written in romanized script.

Vietnamese slang (tiếng lóng) changed from time to time. Vietnamese slang consists of pure Vietnamese words or words borrowed from other languages such as Mandarin or Indo-European languages.[46] It is estimated that Vietnamese slang that originated from Mandarin accounts for a tiny proportion of all Vietnamese slang (4.6% of surveyed data in newspapers).[46] On the contrary, slang that originated from Indo-European languages accounts for a more significant proportion (12%) and is much more common in today's uses.[46] Slang borrowed from these languages can be either transliteration or vernacular.[46] Some examples:

With the rise of the Internet, new slang is generated and popularized through social media. This more modern slang is commonly used among the younger generation in Vietnam. This more recent slang is mostly pure Vietnamese, and almost all the words are homonyms or some form of wordplay. Some examples:

There are debates on the prevalence of uses of slang among young people in Vietnam, as certain teen speak conversations become difficult to understand for older generations. Many critics believed that incorporating teenspeak or internet slang into daily conversation among teenagers would affect the formality and cadence of speech.[52] Others argue that it is not the slang that is the problem but rather the lack of communication techniques for the instant internet messaging era. They believe slang should not be dismissed, but instead, youth should be informed enough to know when to use them and when it is appropriate.[53]

A sign at the Hỏa Lò Prison museum in Hanoi lists rules for visitors in both Vietnamese and English.

After ending a millennium of Chinese rule in 938, the Vietnamese state adopted Literary Chinese (called văn ngôn 文言 or Hán văn 漢文 in Vietnamese) for official purposes.[54] Up to the late 19th century (except for two brief interludes), all formal writing, including government business, scholarship and formal literature, was done in Literary Chinese, written with Chinese characters (Chữ Hán).[55]

From around the 13th century, Vietnamese scholars used their knowledge of the Chinese script to develop the chữ Nôm (lit.'Southern characters') script to record folk literature in Vietnamese. The script used Chinese characters to represent both borrowed Sino-Vietnamese vocabulary and native words with similar pronunciation or meaning. In addition, thousands of new compound characters were created to write Vietnamese words using a variety of methods, including phono-semantic compounds.[56] For example, in the opening lines of the classic poem The Tale of Kieu,

Nôm writing reached its zenith in the 18th century when many Vietnamese writers and poets composed their works in Nôm, most notably Nguyễn Du and Hồ Xuân Hương (dubbed "the Queen of Nôm poetry"). However, it was only used for official purposes during the brief Hồ and Tây Sơn dynasties.[57]

A Vietnamese Catholic, Nguyễn Trường Tộ, unsuccessfully petitioned the Court suggesting the adoption of a script for Vietnamese based on Chinese characters.[58] The French colonial administration sought to eliminate the Chinese writing system, Confucianism, and other Chinese influences from Vietnam by getting rid of Nôm.[59]

A romanization of Vietnamese was codified in the 17th century by the Avignonese Jesuit missionary Alexandre de Rhodes (1591–1660), based on works of earlier Portuguese missionaries, particularly Francisco de Pina, Gaspar do Amaral and Antonio Barbosa.[60][61] Still, chữ Nôm was the dominant script in Vietnamese Catholic literature for more than 200 years.[62] Starting from the late 19th century, the Vietnamese alphabet (chữ Quốc ngữ or "national language script") was gradually expanded from its initial usage in Christian writing to become more popular among the general public.

The Vietnamese alphabet contains 29 letters, including one digraph (đ) and nine with diacritics, five of which are used to designate tone (i.e. à, á, , ã, and ) and the other four used for separate letters of the Vietnamese alphabet (ă, â/ê/ô, ơ, ư).[63]

This Romanized script became predominant over the course of the early 20th century, when education became widespread and a simpler writing system was found to be more expedient for teaching and communication with the general population. Under French colonial rule, French superseded Chinese in administration. Vietnamese written with the alphabet became required for all public documents in 1910 by issue of a decree by the French Résident Supérieur of the protectorate of Tonkin. In turn, Vietnamese reformists and nationalists themselves encouraged and popularized the use of chữ quốc ngữ. By the middle of the 20th century, most writing was done in chữ quốc ngữ, which became the official script on independence.

Nevertheless, Chữ Hán was still in use during the French colonial period and as late as World War II was still featured on banknotes,[64][65] but fell out of official and mainstream use shortly thereafter. The education reform by North Vietnam in 1950 eliminated the use of chữ Hán and chữ Nôm.[66] Today, only a few scholars and some extremely elderly people are able to read chữ Nôm or use it in Vietnamese calligraphy. Priests of the Gin minority in China (descendants of 16th-century migrants from Vietnam) use songbooks and scriptures written in chữ Nôm in their ceremonies.[67]

Chữ quốc ngữ reflects a "Middle Vietnamese" dialect that combines vowels and final consonants most similar to northern dialects with initial consonants most similar to southern dialects. This Middle Vietnamese is presumably close to the Hanoi variety as spoken sometime after 1600 but before the present. (This is not unlike how English orthography is based on the Chancery Standard of Late Middle English, with many spellings retained even after the Great Vowel Shift.)

The Unicode character set contains all Vietnamese characters and the Vietnamese currency symbol. On systems that do not support Unicode, many 8-bit Vietnamese code pages are available such as (VSCII) or Windows-1258. Where ASCII must be used, Vietnamese letters are often typed using the VIQR convention, though this is largely unnecessary with the increasing ubiquity of Unicode. There are many software tools that help type Roman-script Vietnamese on English keyboards, such as and on Windows, or on Macintosh, with popular methods of Vietnamese using Telex, VNI or VIQR input methods. Telex input method is often set as the default for many devices.

Vietnamese speak date in the format "day month year". Each month's name is just the ordinal of that month appended after the word tháng, which means "month". Traditional Vietnamese however assigns other names to some months; these names are mostly used in the lunar calendar and in poetry.

The Vietnamese prefer writing numbers with a comma as the decimal separator in lieu of dots, and either spaces or dots to group the digits. An example is 1 629,15 (one thousand six hundred twenty-nine point fifteen). Because a comma is used as the decimal separator, a semicolon is used to separate two numbers instead.

The Tale of Kieu is an epic narrative poem by the celebrated poet Nguyễn Du, (), which is often considered the most significant work of Vietnamese literature. It was originally written in Chữ Nôm (titled Đoạn Trường Tân Thanh 斷腸) and is widely taught in Vietnam (in chữ quốc ngữ transliteration).

The Vietnamese language has several mutually intelligible regional varieties:[i]

Vietnamese has traditionally been divided into three dialect regions: North, Central, and South. Michel Ferlus and Nguyễn Tài Cẩn also proved that there was a separate North-Central dialect for Vietnamese as well. The term Haut-Annam refers to dialects spoken from the northern Nghệ An Province to the southern (former) Thừa Thiên Province that preserve archaic features (like consonant clusters and undiphthongized vowels) that have been lost in other modern dialects.

These dialect regions differ mostly in their sound systems (see below), but also in vocabulary (including basic vocabulary, non-basic vocabulary, and grammatical words) and grammar.[j] The North-central and Central regional varieties, which have a significant number of vocabulary differences, are generally less mutually intelligible to Northern and Southern speakers. There is less internal variation within the Southern region than the other regions due to its relatively late settlement by Vietnamese speakers (around the end of the 15th century). The North-central region is particularly conservative; its pronunciation has diverged less from Vietnamese orthography than the other varieties, which tend to merge certain sounds. Along the coastal areas, regional variation has been neutralized to a certain extent, while more mountainous regions preserve more variation. As for sociolinguistic attitudes, the North-central varieties are often felt to be "peculiar" or "difficult to understand" by speakers of other dialects, despite the fact that their pronunciation fits the written language the most closely; this is typically because of various words in their vocabulary which are unfamiliar to other speakers (see the example vocabulary table below).

The large movements of people between North and South beginning in the mid-20th century and continuing to this day have resulted in a sizable number of Southern residents speaking in the Northern accent/dialect and, to a greater extent, Northern residents speaking in the Southern accent/dialect. Following the Geneva Accords of 1954 that called for the temporary division of the country, about a million northerners (mainly from Hanoi, Haiphong and the surrounding Red River Delta areas) moved south (mainly to Saigon and heavily to Biên Hòa and Vũng Tàu, and the surrounding areas) as part of Operation Passage to Freedom. About 18% (~180,000) of that number of people made the move in the reverse direction (Tập kết ra Bắc, literally "go to the North".)

Following the reunification of Vietnam in 1975, Northern and North-Central speakers from the densely populated Red River Delta and the traditionally poorer provinces of Nghệ An, Hà Tĩnh, and Quảng Bình have continued to move South to look for better economic opportunities, beginning with the new government's "New Economic Zones program" which lasted from 1975 to 1985.[68] The first half of the program (1975–80), resulted in 1.3 million people sent to the New Economic Zones (NEZs), majority of which were relocated to the southern half of the country in previously uninhabited areas, of which 550,000 were Northerners.[68] The second half (1981–85) saw almost 1 million Northerners relocated to the NEZs.[68] Government and military personnel from Northern and North-central Vietnam are also posted to various locations throughout the country, often away from their home regions. More recently, the growth of the free market system has resulted in increased interregional movement and relations between distant parts of Vietnam through business and travel. These movements have also resulted in some blending of dialects, but more significantly, have made the Northern dialect more easily understood in the South and vice versa. Most Southerners, when singing modern/old popular Vietnamese songs or addressing the public, do so in the standardized accent if possible (which is Northern pronunciation). This is true in Vietnam as well as in overseas Vietnamese communities.

Modern Standard Vietnamese is based on the Hanoi dialect. Nevertheless, the major dialects are still predominant in their respective areas and have also evolved over time with influences from other areas. Historically, accents have been distinguished by how each region pronounces the letters d ([z] in the Northern dialect and [j] in the Central and Southern dialect) and r ([z] in the Northern dialect, [r] in the Central and Southern dialects). Thus, the Central and Southern dialects can be said to have retained a pronunciation closer to Vietnamese orthography and resemble how Middle Vietnamese sounded in contrast to the modern Northern (Hanoi) dialect which underwent shifts.

Although regional variations developed over time, most of these words can be used interchangeably and be understood well, albeit, with more or less frequency then others or with slightly different but often discernible word choices and pronunciations.

The syllable-initial ch and tr digraphs are pronounced distinctly in North-Central, Central, and Southern varieties, but are merged in Northern varieties (i.e. they are both pronounced the same way). Many North-Central varieties preserve three distinct pronunciations for d, gi, and r whereas the North has a three-way merger and the Central and South have a merger of d and gi while keeping r distinct. At the end of syllables, palatals ch and nh have merged with alveolars t and n, which, in turn, have also partially merged with velars c and ng in Central and Southern varieties.

In addition to the regional variation described above, there is a merger of l and n in certain rural varieties in the North:[70]

Variation between l and n can be found even in mainstream Vietnamese in certain words. For example, the numeral "five" appears as năm by itself and in compound numerals like năm mươi "fifty" but appears as lăm in mười lăm "fifteen" (see Vietnamese grammar#Cardinal). In some northern varieties, this numeral appears with an initial nh instead of l: hai mươi nhăm "twenty-five", instead of mainstream hai mươi lăm.[m]

There is also a merger of r and g in certain rural varieties in the South:

The consonant clusters that were originally present in Middle Vietnamese (of the 17th century) have been lost in almost all modern Vietnamese varieties (but retained in other closely related Vietic languages). However, some speech communities have preserved some of these archaic clusters: "sky" is blời with a cluster in Hảo Nho (Yên Mô, Ninh Bình Province) but trời in Southern Vietnamese and giời in Hanoi Vietnamese (initial single consonants /ʈ/, /z/, respectively).

Although there are six tones in Vietnamese, some tones may slightly[clarification needed] "merge", but are still highly distinguishable due to the context of the speech.[clarification needed] The hỏi and ngã tones are distinct in North and some North-central varieties (although often with different pitch contours) but have somewhat[clarification needed] merged in Central, Southern, and some North-Central varieties (also with different pitch contours). Some North-Central varieties (such as Hà Tĩnh Vietnamese) have a slight[clarification needed] merger of the ngã and nặng tones while keeping the hỏi tone distinct. Still, other North-Central varieties have a three-way merger of hỏi, ngã, and nặng resulting in a four-tone system. In addition, there are several phonetic differences (mostly in pitch contour and phonation type) in the tones among dialects.

The table above shows the pitch contour of each tone using Chao tone number notation (where 1 represents the lowest pitch, and 5 the highest); glottalization (creaky, stiff, harsh) is indicated with the ⟨◌̰⟩ symbol; murmured voice with ⟨◌̤⟩; glottal stop with ⟨ʔ⟩; sub-dialectal variants are separated with commas. (See also the tone section below.)

A language game known as nói lái is used by Vietnamese speakers.[71] Nói lái involves switching/adding/removing the tones in a pair of words and also the order of the two words or the first consonant and rime of each word; the resulting nói lái pair preserves the original sequence of tones. Some examples:

The resulting transformed phrase often has a different meaning but sometimes may just be a nonsensical word pair. Nói lái can be used to obscure the original meaning and thus soften the discussion of a socially sensitive issue, as with dấm đài and hoảng chưa (above) can you please NG VÀ NIKITA CA MÌNH CÓ or, when implied (and not overtly spoken), to deliver a hidden subtextual message, as with bồi tây.[n] Naturally, nói lái can be used for a humorous effect.[72]

Another word game somewhat reminiscent of pig latin is played by children. Here a nonsense syllable (chosen by the child) is prefixed onto a target word's syllables, then their initial consonants and rimes are switched with the tone of the original word remaining on the new switched rime.

This language game is often used as a "secret" or "coded" language useful for obscuring messages from adult comprehension.