Vowels

• All vowels have nasal counterparts, represented by "~" in IPA and ँ on the vowels, like आँ [ãː] .
• All vowel sounds are realised as nasal when occurring before or after a nasal consonant.^[3]
• Word final अ [a] is always deleted, except in monosyllabic words, non-syllabic (य /e̯/ and /o̯/) final words (if preceded by any non-central vowel) and conjunct final words. In the middle position, it is shortened to [^a] /ə̆/, if unstressed. Both extra short vowel and deleted vowel are pronounced in poetry though.
• Ramavatar Yadav ignores the contrast between short and long vowels, as its length is often determined by position.^[3] Others maintain the contrast as some of the differences can be explained by position, but not all.
• Sounds [eː] and [oː] are often replaced by diphthongs [əɪ̯] and [əʊ̯] in various dialects.^{[citation needed]}
• [ɔ] is realised as [əː] in northern dialects and o in southernmost dialects.
• There are three extra short vowels that were described by Grierson, अ [ ə̆ ] (Rom. as a ), इ' [ ɪ̆ ] (Rom. as i), उ' [ ʊ̆ ] (Rom. as u), but are not counted by Ramavatar Yadav and other modern grammarians. The first could be understood as syllable break: ( "." in IPA).
• A peculiar type of phonetic change is recently taking place in Maithili by way of epenthesis, i.e. backward transposition of final extra short i and u in all sort of words.^[4] Thus:

Standard Colloquial - Common Pronunciation

अछि' / achⁱ / - अइछ / aich / 'is'

मधु' / madh^u / - मउध / maudh / 'honey'

बालु' / bāl^u / - बाउल / bāul / 'sand'

Only extra short i and u have been applicable for this rule, however recently short i and u have started to observe same pattern, though it is very scattered, and non-standard-

रवि / rabi / - रइब / raib / 'Sunday'

This phenomenon is observed only in northern dialects, in southern dialects it is often maintained or even lengthened.

achⁱ→(a)chī

madh^u→madhū

bāl^u→bālū

rabi→rabī

• ꣾ is a Unicode letter in Devanagari, (IPA /əe̯/) which is not supported currently on several browsers and operating systems, along with its mātrā (vowel sign).

The following diphthongs are present:^[4]

अय़/ꣾ / əe̯ / ~ /ɛː/ - अय़सन/ꣾसन /aisan/ ~ /êsan/ 'like this'

अव़/ॵ / əo̯ / ~ /ɔː/- चव़मुख/चॏमुख /caumukh/ ~ /cåmukh/ 'four faced'

अऎ /ꣾ əe̯ / - अऎलाह/ꣾलाह /aelah/ 'came'

अऒ/ॵ / əo̯ / - अऒताह/ॵताह /aotah/ 'will come'

आइ / aːi̯ / - आइ /āi/ 'today'

आउ / aːu̯ / - आउ /āu/ 'come please'

आऎ / aːe̯ / - आऎल /āel/ 'came'

आऒ / aːo̯ / - आऒब /āob/ 'will come'

यु/इउ / iu̯/ - घ्यु/घिउ /ghiu/ 'ghee'

यॆ/इऎ / ie̯ / - यॆह/इऎह /ieh/ 'only this' (dialectical variation of इहꣿ/यꣿह)

यॊ/इऒ / io̯ / - कह्यो/कहिऒ /kahio/ 'any day'

वि/उइ / ui̯ / - द्वि/दुइ /dui/ 'two'

वॆ/उऎ /ue̯/ - वॆह/उऎह /ue:h/ 'only that' (dialectical variation of उहꣿ/वꣿह)

There are some graphemes, borrowed from Sanskrit, which are written as pronounced in Sanskrit-

Consonants

Maithili has four classes of stops, one class of affricate, which is generally treated as a stop series, related nasals, fricatives and approximant.

• Fricative sounds [ʂ, ɕ] only occur marginally, and are typically pronounced as a dental fricative /s/ in most styles of pronunciation.^[8] Both are defective phonemes, occurring intervocalically and word finally only if preceded by a nasal consonant. Word finally and postvocalically, /ɖʱ/ surfaces as [ɽʱ~rʱ].[h] always occurs postvacalically.
• Word finally and postvocalically, /ɖʱ/ surfaces as [ɽʱ~rʱ].^[9] Non-initially, both are interchangeable with [ɽ~ɾ] and [ɽʱ~rʱ] respectively.^[8]
• Approximant sounds [ʋ, w, j] and fricative sounds [ɸ, f, z, ɕ, ʃ, ʒ, ʂ, x], mainly occur in words that are borrowed from Sanskrit or in words of Perso-Arabic origin. [v,w] are replaced by [b]. Word initial [ʋ,b] can be replaced by [o] in non-tatsama words. Word initial [j], and [j] between [r/ɾ] and central vowels are replaced by [j] in tatsama words, and in rest [e]. Word initial [j] can be replaced by ['i] in non-tatsama words. Both [j] and [ʋ/w] can occur due to glide formation. Perso-Arabic and fricatives [f, z, ʃ, ʒ, x] are generally replaced by [pʰ, d͡ʒ, s, d͡ʒ, kʰ] respectively, in writing also, whereas Sanskrit [ɕ, ʂ) are replaced by [s], but only in speech, in writing, Sanskrit spelling is often followed. [ɸ~f] and [x] are the occurrences of remnants of Sanskrit jihvamuliya and upadhmaniya. The conjunct [ʂp] is pronounced [ɸp] in Maithili e.g. [pʊɸp(ə)]. The conjunct [ɦj] is pronounced [ɦʑ] as in [graːɦʑə].^[8]

These non-syllabic vowels in Maithili- e̯, o̯ written in Devanagari as य़, व़. Most of the times, these are written without nukta.

Stress

Stress is not as strong in Maithili as in English.^[1][8] It is useful for determining the pronunciation of अ [a] though. The stress is not indicated in writing in native scripts, though indicated in this section.

• Final unpronounced अ [a→∅], final extra short इ' [ⁱ] and उ' [^u] are not considered for counting syllables for determining the position of stress. Conjunct consonants are considered long.^[8]
• Monosyllabic words have the accent on the single vowel. As in न ˈna not, ई ˈī this, के ˈkē who, and माछ ˈmāch fish.^[1]
• The accent falls on the final vowel, if it is long and closed (i.e. followed by a consonant or consonant cluster). As in किसा॔न kiˈsān farmer, दॆखलिꣾ॔न्हि' dekh^aliˈainhⁱ I saw (object - 3PHon.), and दॆखलहू॔न्हि' dekh^alaˈhūnhⁱ You saw (object - 3PHon.).^[8]
• The accent falls on the penultimate (i.e. the word being vowel final), if it is long. As in पा॔नि ˈpāni water, and छॊट॔क्का choˈṭakkā small (adj. long form).^[8]
• In non-tatsama words, the accent falls on the antepenultimate in the rest of the cases. As in ह॔मरा ˈham^arā me, and दॆ॔खलहुँ ˈdekh^alahũ I saw.^[8]
• In tatsama words, the accent falls on the vowel before the antepenultimate. It may alternatively be on the antepenultimate. कु॔टिलता ˈkuṭilatā or कुटि॔लता kuˈṭil^atā deceitfulness.^[8]
• If the initial vowel doesn't have a primary accent (as explained above), it carries a secondary accent. As in कि॓सा॔न ˌkiˈsān, दॆ॓खलिꣾ॔न्हि' ˌdekh^aliˈainhⁱ, छॊ॓ट॔क्का ˌchoˈṭakkā, कु॓टि॔लता ˌkuˈṭil^atā.^[8]
• Words with a final इ' [ⁱ] and उ' [^u] always have secondary accent on the preceding vowel, if it doesn't have the primary accent. As in दॆ॔ख॓थि' ˈdēˌkhathⁱ or ˈdeˌkhaith he/she (Hon.) saw, क॔कर॓हुँ' ˈkak^aˌrah^ũ or kˈak^arˌaũh anyone (acc.), दॆ॔खल॓हुँ' ˈdekh^aˌlah^ũ or ˈdekh^aˌlaũh I saw.^[8]
• Causative verbs, whether finite or non-finite, have the primary accent on the final vowel of the root verb, if it has four ir less syllables. If more syllables, then it is optional, it may be stressed if it needs to be stressed. As in ह॓टा॔ऎब ˌhaˈtāeb to remove (infinitive)/ I will remove, but प॓हुँच◌ꣿलथी॔न्हि' ˌpahũcăel^athˈīnhⁱ or प॓हुँचऻ॔ꣾलथीन्हि' ˌpahũcăˈel^athīnhⁱ he/she (Hon.) sent.^[1]
• अ [a], if unstressed, is always deleted word finally. It is shortened to [^a], in other positions, but may be retained if it is not just after the stressed vowel. As in कु॔टिलता ˈkuṭilatā deceitfulness. Here [a] after [l] is retained, even though it is unstressed.

Rule of the Short Antepenultimate^[8]

This peculiar rule was first observed by Hoernle, but properly described by Grierson. It is a very important and essential rule for Maithili and other Bihari languages.

• For this rule the final unpronounced अ [a→∅], final extra short इ' [ⁱ] and उ' [^u] are not considered for counting syllables, and diphthongs are considered as separate syllables, except for the verbal suffices ꣾ [ai] ॵ [au], which are otherwise considered as अइ and अउ for this rule.
• Any long monophthong, in antepenultimate position is shortened, if it is not followed by the euphonics य or व/अ (pronounced [a]).^[10] As in बऻतिया bătiyā (the talk), ॴगिया ăgiyā (the fire), नऻउआ/नॏआ năuā (the barber), मऻरलक măr^alak (he/she/it killed/beaten), सिखलक sikh^alak (he/she/it learned), दॆखलक dekh^alak (he/she/it saw), सुतलन्हि' sut^alanhⁱ (he/she slept), but सीयलक sīalak (he/she/it sewed), चूअलऻह cualăh (it/he/she dripped).
• ॴ [ā] is often replaced by अ [a], when there is no confusion in meaning. As in बऻतिया/बतिया bătiyā/batiyā, and ॴगिया/अगिया ăgiya/agiyā. In verbs, the difference between the two is very important for the difference in the meaning. As in मऻरलहुँ' măr^alah^ũ (I killed) v/s मरलहुँ mar^alah^ũ (I was killed). In verbs, therefore the difference is always maintained.
• Any long monophthong in a position further removed from antepenultimate position is always shortened, whether followed by euphonic syllable or not. As in चुअलक◌ꣿ cualakai (it/he/she dripped), हॊइꣾ hoiai (I become), दॆखितिॵ dekhitiau (if I had seen you (Non-Hon.)).
• Doubled consonants are shortened to single, and the vowel before nasal conjuncts are nasalised, and the nasal consonant is removed, or alternatively the conjunct is converted to the corresponding nasal consonant, if they are to be shortened. As in छॊटकवा choṭak^avā (small), बँधुआ bãdhuā or बन्हुआ banhuā (bound).

Nouns

Nouns in Maithili can be roughly characterized into four genders- Masculine, Feminine, Neuter and Common.^[11] Unmarked nouns can be of any gender. Marked nouns are those nouns, which can be distinguished by its suffix. Marked nouns are mostly either Masculine-neuter or Feminine.(Masculine and neuter, and sometimes even common gender are distinguished, if the word is of tatsama origin). There is no grammatical gender however, i.e. nouns can be distinguished by the suffix in the marked nouns, and overall by the origin of the word, but that doesn't affect other parts of speech. (There are some forms, but are optional and obsolete, and are generally ignored in recent times). The only instance, where grammatical agreement occurs are adjectives, which are also optional, and in spoken language, often ignored altogether.

Similarly, grammatical number is also absent. There are some forms of plural present, but there is no grammatical distinction. Periphrastic plural is used, but again there is no grammatical distinction.

Many Maithili nouns usually take forms in weak (ending in a consonant, a short vowel, or an extra short vowel) and strong stem (ending in long vowels). Some take form only in weak stem and some in strong stem.

The following table shows a general view of them. Obsolete and old forms are shown within parentheses, in the stem ending ending section.

Key: M- Masculine, F- Feminine, N- Neuter gender ∅- No addition to the stem, ×- No form exists

• *Some stems in "i" and "u" don't have long forms in common sense, but they have a plural in long vowel, such as पानी pānī for पानि pāni (water), and आँसू ā̃sū for आँसु ā̃su (tear). Since Maithili doesn't have a strong distinction of grammatical number, these are treated in various ways. In forms which are less likely to have plural, and most of the tatsama words, like रवि ravi (sun), वसु vasu (the vasus) don't use the strong stem, whereas things which are mostly plural like आँसू ā̃sū (tears) and दाढ़ी dāḍhī (beard) tend to use the strong stem. Some use both such पानि pāni and पानी pānī (water), दहि dahi and दही dahī (curd).

• **इ' -i and उ' -u are postvacalically इ -i and उ -u respectively.

Gender

Gender in Maithili is generally not in agreement, though it can be identified through suffixes. Some masculine nouns are converted to feminine using suffixes, others are common for both the genders. Neuter is sometimes separate from Masculine. Some neuters are diminutive and are marked like feminine. Both tadbhava and tatsama suffixes are used for different words of different origin.

Adpositions

The aforementioned inflectional case system only goes so far on its own, and rather serves as that upon which is built a system of agglutinative suffixes or particles known as postpositions or Case markers. It is their use with a noun or verb that necessitates the noun taking the oblique case, and it is with them that the locus of grammatical function or "case-marking" then lies.

Definiteness is also marked in Maithili using prepositions and postpositions. The accusative marker kē̃ केँ is not used always, it is used in specific conditions^[1]-

Some other postpositions are-

• Some postpositions are added to the genitive too, and sometimes the genitive inflection is not used at all, except in pronominal inflection.

• Plural is made using postpositions, and also by preposition having a sense of completeness.

First and Second Person Pronouns^[1]

Third Person Pronouns^[1]