Hindi-Urdu phonology

Hindustani is the lingua franca of northern India and Pakistan, and through its two standardized registers, Hindi and Urdu, an official language of India and Pakistan. Phonological differences between the two standards are minimal.

Hindustani natively possesses a symmetrical ten-vowel system. The vowels: [ə], [ɪ], [ʊ] are always short in length, while the vowels: [ɑː, iː, uː, eː, oː, ɛː, ɔː] are always considered long (but see the details below). /ə/ is often realized more open than mid [ə], i.e. as near-open [ɐ]. The open central vowel is transcribed in IPA by either [aː] or [ɑː]. Among the close vowels, what in Sanskrit are thought to have been primarily distinctions of vowel length (that is /i ~ iː/ and /u ~ uː/), have become in Hindustani distinctions of quality, or length accompanied by quality (that is, /ɪ ~ iː/ and /ʊ ~ uː/). The historical opposition of length in the close vowels has been neutralized in word-final position, for example Sanskrit loans śakti (शक्ति – شَکتی 'energy') and vastu (वस्तु – وَستُو 'item') are /ʃəkt̪i/ and /ʋəst̪u/, not */ʃəkt̪ɪ/ and */ʋəst̪ʊ/.

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