Phonetic Analysis Of Tianjin Students' Mispronunciation Of English Vowel [e],[(?)] And [ai]

This thesis focuses on the mispronunciation of vowels [e], [(?)] and [ai] made by Tianjin learners of English. Six English professors in Tianjin Normal University judge the pronunciations of ten English learners in different colleges. Three subjects are singled out to do phonetics experiment because their correctness is the lowest. The spectrogram of every word is made. The reasons why Chinese students mispronounce these vowels are provided.The main results of the study arc as the following:1.The influence of quality of Chinese /ai/: If the pronunciation of Chinese /ai/ or the first part of Chinese diphthong /ai/ is similar to English monophthong [(?)] or [e], the transfer of Chinese can help learners to make English monophthong [(?)] or [e]. If the pronunciation of Chinese /ai/ is similar to English diphthong [ai], the transfer of Chinese can help learners to make English [ai].2.The influence of distributions of Chinese vowels: Because of the difference of Chinese /ai/ and English {ai} they mispronounce [ai] as [(?)i] or a monophthong. 3. The influence of onset and coda in the syllable: A open syllable (no coda): Chinese /ai/ appears only in open syllable. Therefore learners tend to pronounce monophthongs as [ai] in open syllable and they usually have no problem in pronouncing [ai] correctly. B closed syllable (simple coda): Chinese students usually diminish the length of vowels when they are in a closed syllable. So some students will have trouble in making correct [ai]. When the onset of the syllable is [d] and so on, speakers have more chances to make a monophthong. But some succeed to pronounce [ai] if the onset is [h] and so on. C closed syllable (complex coda or schwa): Very few students can manage to pronounce [ai] correctly. Diphthong [ai] is pronounced as monophthong [e] or [as]. On the contrary very few [e] or [(?)] followedby complex coda is mispronounced as [ai |.