Bengali phonology
The phonology of Bengali, like that of its neighbouring Eastern Indo-Aryan languages, is characterised by a wide variety of diphthongs and inherent back vowels.
Phonemic inventory
Phonemically, Bengali features 29 consonants, 7 oral vowels, and up to 7 nasalized vowels. In the tables below, the sounds are given in IPA.| Front | Central | Back | |
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Although the standard form of Bengali is largely uniform across Bangladesh and India, there are a few sounds that vary in pronunciation :
Consonant clusters
Native Bengali words do not allow initial consonant clusters; the maximum syllabic structure is CVC. Many speakers of Bengali restrict their phonology to this pattern, even when using Sanskrit or English borrowings, such as গেরাম geram for গ্রাম gram meaning 'village' or ইস্কুল iskul / ishkul for স্কুল skul 'school'.Sanskrit words borrowed into Bengali, however, possess a wide range of clusters, expanding the maximum syllable structure to CCCVC. Some of these clusters, such as the in মৃত্যু mrittu or the in স্পষ্ট spôshṭo, have become extremely common, and can be considered permitted consonant clusters in Bengali. English and other foreign borrowings add even more cluster types into the Bengali inventory, further increasing the syllable capacity, as commonly used loanwords such as ট্রেন ṭren and গ্লাস glash are now included in leading Bengali dictionaries.
Final consonant clusters are rare in Bengali. Most final consonant clusters were borrowed into Bengali from English, as in লিফ্ট lifṭ and ব্যাংক beņk. However, final clusters do exist in some native Bengali words, although rarely in standard pronunciation. One example of a final cluster in a standard Bengali word would be গঞ্জ gônj, which is found in names of hundreds of cities and towns across Bengal, including নবাবগঞ্জ Nôbabgônj and মানিকগঞ্জ Manikgônj. Some nonstandard varieties of Bengali make use of final clusters quite often. For example, in some Purbo dialects, final consonant clusters consisting of a nasal and its corresponding oral stop are common, as in চান্দ chand. The Standard Bengali equivalent of chand would be চাঁদ chãd, with a nasalized vowel instead of the final cluster.
Diphthongs
Magadhan languages such as Bengali are known for their wide variety of diphthongs, or combinations of vowels occurring within the same syllable. Two of these, and, are the only ones with representation in script, as ঐ and ঔ respectively. The semivowels may all form the glide part of a diphthong. The total number of diphthongs is not established, with bounds at 17 and 31. Several vowel combinations can be considered true monosyllabic diphthongs, made up of the main vowel and the trailing vowel. Almost all other vowel combinations are possible, but only across two adjacent syllables, such as the disyllabic vowel combination in কুয়া . As many as 25 vowel combinations can be found, but some of the more recent combinations have not passed through the stage between two syllables and a diphthongal monosyllable.Prosody
Stress
In standard Bengali, stress is predominantly initial. Bengali words are virtually all trochaic; the primary stress falls on the initial syllable of the word, while secondary stress often falls on all odd-numbered syllables thereafter, giving strings such as সহযোগিতা sahayogitā . The first syllable carries the greatest stress, with the third carrying a somewhat weaker stress, and all following odd-numbered syllables carrying very weak stress. However, in words borrowed from Sanskrit, the root syllable has stress, out of harmony with the situation with native Bengali words. Also, in a declarative sentence, the stress is generally lowest on the last word of the sentence.Adding prefixes to a word typically shifts the stress to the left; for example, while the word সভ্য sabhya carries the primary stress on the first syllable, adding the negative prefix creates অসভ্য asabhya, where the primary stress is now on the newly added first syllable অ ô. Word-stress does not alter the meaning of a word and is always subsidiary to sentence-level stress.
Intonation
For Bengali words, intonation or pitch of voice have minor significance, apart from a few cases such as distinguishing between identical vowels in a diphthong. However, in sentences intonation does play a significant role. In a simple declarative sentence, most words and/or phrases in Bengali carry a rising tone, with the exception of the last word in the sentence, which only carries a low tone. This intonational pattern creates a musical tone to the typical Bengali sentence, with low and high tones alternating until the final drop in pitch to mark the end of the sentence.In sentences involving focused words and/or phrases, the rising tones only last until the focused word; all following words carry a low tone. This intonation pattern extends to wh-questions, as wh-words are normally considered to be focused. In yes–no questions, the rising tones may be more exaggerated, and most importantly, the final syllable of the final word in the sentence takes a high falling tone instead of a flat low tone.
Vowel length
Like most Magadhan languages, vowel length is not contrastive in Bengali; all else equal, there is no meaningful distinction between a "short vowel" and a "long vowel", unlike the situation in most Indo-Aryan languages. However, when morpheme boundaries come into play, vowel length can sometimes distinguish otherwise homophonous words. This is because open monosyllables can have somewhat longer vowels than other syllable types. For example, the vowel in ca can be somewhat longer than the first vowel in caṭa, as ca is a word with only one syllable, and no final consonant. The suffix ṭa can be added to ca to form caṭa, and the long vowel is preserved, creating a minimal pair. Knowing this fact, some interesting cases of apparent vowel length distinction can be found. In general, Bengali vowels tend to stay away from extreme vowel articulation.Furthermore, using a form of reduplication called "echo reduplication", the long vowel in ca can be copied into the reduplicant ṭa, giving caṭa. Thus, in addition to caṭa with a longer first vowel and caṭa with no long vowels, we have caṭa with two longer vowels.
Regional phonological variations
Affricates and fricatives
In the dialects prevalent in much of eastern and south-eastern Bangladesh, and Tripura and Barak Valley of India, many of the stops and affricates heard in the western and central dialects are pronounced as fricatives. Western palato-alveolar and alveolo-palatal affricates চ, ছ, জ, ঝ correspond to eastern চ়, স, জ়, য . Note that few Perso-Arabic borrowings containing the phoneme are realised as such in all dialects.The unvoiced aspirated velar stop খ, the aspirated labial stop ফ and the voiced aspirated labial stop ভ of western-central Bengali dialects correspond to খ়, ফ় and ভ় in eastern Bengali. These pronunciations are more prevalent in the Sylheti variety of northeastern Bangladesh and south Assam, the variety spoken by most of the Bengali community in the United Kingdom. Note that phonemic transcriptions from left to right for eastern Bengali dialects indicate the realizations further eastwards. Retroflexes lose aspiration and variously remain like that or become alveolar. Breathy voiced stops lose breathiness. The voiced velar stop গ can fricative to গ়, and is mostly lost afterwards. The stops ঘ থ ধ ঠ ঢ are relatively stable across dialects that do not lose aspiration, remaining . The first 3 stops may be phonetically realised as affricates by a few speakers, though this is extremely rare and idiosyncratic. থ and দ in English loanwords fricatise to থ় and দ় respectively in the speech of educated speakers, though this realisation isn't used in native words.
Many eastern Bengali dialects share phonological features with Assamese, including the debuccalisation of স, শ & ষ to হ .
Substrate and Tibeto-Burman influence
The influence of older substrate and Tibeto-Burman languages on the phonology is more observable in eastern Bengali dialects, and becomes increasingly prominent eastwards. In dialects of the Mymensingh, Sylhet, Chittagong Divisions of Bangladesh, and Tripura and Barak Valley of India, alveolar stops are realised in place of postalveolar stops ট, ঠ, ড, and ঢ, resembling the equivalent phonemes in Southeast Asian languages such as Thai and Lao.In the phonology of far western Bengali, the distinction between the alveolar tap র, and postalveolar taps ড় and ঢ় is clear and distinct like Indian languages further west. However, the distinction is often less clear in western and central dialects, and fully lost in eastern dialects, where both tap sounds are realised as either the alveolar tap or the alveolar approximant, similar to Assamese ৰ, due to older substrate and Tibeto-Burman influence. Far eastern Bengali dialects tend not to distinguish aspirated voiced stops ঘ, ঝ, ঢ, ধ, and ভ from their unaspirated equivalents, with some dialects treating them as allophones of each other and other dialects replacing the former with the latter completely. Note that ঢ় is realised as but not as in all Bengali dialects except for far western ones.
Some variants of the Bengali, particularly the Chittagonian, Noakhailla and Sylheti, have contrastive tone and so differences in pitch can distinguish words. There is also a distinction between ই and ঈ in many northern Bangladeshi Bengali dialects. ই represents the uncommon, but ঈ the standard used for both letters in most other dialects.