The Effects Of Vowels And Nasals On The Discrimination Of Alveolar And Velar Nasal-Rhymes In Mandarin

Since the Scheme for Chinese Pinyin was implemented in 1958,the classification of nasal vowels has been systematically adjusting in textbooks,and it now has a consensus system.It is generally believed that the three groups of nasal-rhymes,‘an’and ‘ang’,‘en’ and ‘eng’,and ‘in’ and ‘ing’,are most easily confused in speech,and the distinction between the nasals rather than vowels in these three pairs is often emphasised in Mandarin teaching.However,even though these nasal-rhymes each have vowels with the same spelling and the vowels belong to the same phoneme,according to the assimilation theory and phonetic measurement,their vowel values are quite different.Therefore,the vowels of the same pair of alveolar and velar nasalrhymes can also be distinguished from each other theoretically,but there is not many researches that have been conducted to verify it.This study used the nasal-rhyme audios processed by the phonetic software Praat to carry out the perception experiments,in which 19 subjects participated.The thesis analyses the experimental results,discussing the role of vowels and nasals in the perception and examining the influence of other factors in the syllables on discrimination.In addition,this paper also tries to find out the effect of the differences in subjects’ language ability on the experimental results.The nasal-deletion perception experiment shows that the subjects could basically distinguish whether a nasal-rhyme is an alveolar one or a velar one only by the vowel part of the nasal-rhyme;while the result of the nasal-replacement perception experiment is that when the vowel of a nasal-rhyme does not match the nasal,the subjects tend to judge the nasal-rhyme by the nasal part.In addition,the factors that affect subjects’ choices include the initial consonant(being aspirated or not),the tone of the nasal-rhyme,the second formant frequency of the vowels and nasals in the nasal-rhyme,and the duration of the nasal-rhyme.Also,the subjects’ ability of their dialects,Mandarin Chinese,English,and other foreign languages also has a rather strong correlation with the results.The theoretical significance and practical value are as follows.Theoretically,this experiment enriches the perception studies of Chinese nasal-rhymes.It confirms that because the Chinese syllable structure is ‘tight inside and loose outside’,the vowels of the same pair of nasal-rhymes will be affected by the assimilation of subsequent nasals,which can be a cue to discriminate between alveolar and velar nasal-rhymes in perception.Practically,this experimental study provides a new theoretical basis for Chinese nasal-rhyme teaching.When teachers want the learners to learn how to distinguish between a pair of alveolar and velar nasal-rhymes,they can not only emphasize the differences between nasals in nasal-rhymes,but also try to include the difference between tongue positions of vowels and the length of syllables in their teaching,so that learners may master the pronunciation of nasal-rhymes more easily.