Khác biệt giữa các bản “Thanh điệu”

n
n (replaced: VietnameseTiếng Việt, RussianTiếng Nga using AWB)
 
==Tonal polarity==
Languages with simple tone systems or [[pitch accent]] may have one or two syllables specified for tone, with the rest of the word taking a default tone. Such languages differ in which tone is marked and which is the default. In [[Navajo language|Navajo]], for example, syllables have a low tone by default, while marked syllables have high tone. In the related language [[Sekani language|Sekani]], however, the default is high tone, and marked syllables have low tone.<ref>{{chú thích web|url=http://people.umass.edu/jkingstn/web%20page/research/athabaskan%20tonogenesis%20camera%20ready%20final%2021%20october%2004.pdf|title=The Phonetics of Athabaskan Tonogenesis|last=Kingston|first=John|year=2004|work=Athabaskan Prosody|publisher=John Benjamins Press|pages=131–179|accessdate = ngày 14 tháng 11 năm 2008}}</ref> There are parallels with stress: English stressed syllables have a higher pitch than unstressed syllables, whereas in [[RussianTiếng language|RussianNga]], stressed syllables have a lower pitch.
 
==Uses of tone==
Similarly, final [[fricative]]s or other consonants may phonetically affect the pitch of preceding vowels, and if they then [[lenition|weaken]] to /h/ and finally disappear completely, the difference in pitch, now a true difference in tone, carries on in their stead. This was the case with the Chinese languages: Two of the four tones of [[Middle Chinese]], the "rising" and "departing" tones, arose as the [[Old Chinese]] final consonants {{IPA|/ʔ/}} and {{IPA|/s/ → /h/}} disappeared, while syllables that ended with neither of these consonants were interpreted as carrying the third tone, "even". Most dialects descending from Middle Chinese were further affected by a tone [[Phonemic differentiation#Phonemic splits|split]], where each tone split in two depending on whether the initial consonant was voiced: Vowels following an unvoiced consonant acquired a higher tone while those following a voiced consonant acquired a lower tone as the voiced consonants lost their distinctiveness.
 
The same changes affected many other languages in the same area, and at around the same time (AD 1000–1500). The tone split, for example, also occurred in [[Thai language|Thai]], [[VietnameseTiếng language|VietnameseViệt]], and the [[Lhasa]] dialect of [[Tibetan language|Tibetan]].
 
In general, voiced initial consonants lead to low tones, while vowels after aspirated consonants acquire a high tone. When final consonants are lost, a glottal stop tends to leave a preceding vowel with a high or rising tone (although glottalized vowels tend to be low tone, so if the glottal stop causes vowel glottalization, that will tend to leave behind a low vowel), whereas a final fricative tends to leave a preceding vowel with a low or falling tone. Vowel phonation also frequently develops into tone, as can be seen in the case of Burmese.