An Acoustic Study On The English Fricative Production By Chinese Northeastern EFL Learners

Oral communication,as one basic skill for language learners plays an important role in the language learning process.Pronunciation is the foundation of oral communication.Therefore,mastering the correct English pronunciation is an important prerequisite for improving the English proficiency of English learners.However,every language has its unique language rules and systems.So mother language may influence EFL learners‘ L2 acquisition process.Besides,the huge territory of China and varieties of dialects cause more difficulties for Chinese EFL learners in the process of learning English speech sounds.They tend to transfer the native language‘s pronunciation habits to English acquisition process.English fricatives are consonants.Some English fricatives have similarities with Chinese consonants,which makes Chinese EFL learners unable to see their differences and acquire the authentic English pronunciation.This thesis studies the production of English fricatives by Chinese Northeastern EFL learners.The research materials are from the AESOP---CASS Corpus(Asian English Speech Corpus Project---Chinese Academy of Social Sciences).48 participants from Harbin,Changchun and Shenyang(16 participants each city,8 females and 8 males)are selected and their reading materials are the targets of this research.Besides,the same reading materials from 16 native English speakers(Americans,8 females and 8 males)are also chosen as reference.The research materials for each fricative have two speech contexts,including isolated contexts(read in a single word)and continuous contexts(read in a sentence).And the target English fricatives are in the word-initial and word-final positions.In addition,in order to compare the spatial patterns between English fricatives and Chinese similar phonemes,12 Chinese characters were chosen as the contrast.The research adopts acoustic phonetics approaches,using Minispeechlab extracting the acoustic parameters(including center of gravity and dispersion)and make spatial patterns of each fricative.Besides,Praat is used to annotate the reading materials and extract data.By observing the acoustic features of the spectrograms and waveforms,the author analyzes EFL learners‘ pronunciation deviations and explains the reasons.The research questions are as follows:1.What are the similarities and differences of spatial patterns of English fricatives between Northeastern English learners and native English speakers?2.What are the similarities and differences of English fricative duration values between Northeastern English learners and native English speakers?3.What types of the errors the Northeastern English learners make in the English fricative production? What are the possible reasons for the errors?By comparing the spatial patterns of English fricatives produced by native English speakers and Northeastern English learners,we find that the center of gravity of native English speakers is higher than Northeastern English learners and the dispersion of native English speakers is lower than Northeastern English Learners in general.According to the Space Analysis Theory,center of gravity is inversely proportional to the size of the gap between the speech organs and dispersion is directly proportional to the degree of the dispersion of acoustic energy.So the results show that the friction gaps produced by Northeastern English learners are wider than native English speakers and the energy is not centered.In addition,the spatial patterns of English fricatives produced by English learners share similar positions with some similar Chinese consonants,which indicates that English learners‘ fricative production is greatly influenced by their mother language.As for the English fricative duration,firstly,the standard deviation of Northeastern English learners‘ fricative duration values are larger than the native English speakers‘,which means that individual differences among Northeastern English learners are bigger than those of native English speakers.In addition,the duration values between voiceless and voiced English fricatives by Northeastern English learners have slight differences while the native English speakers produce bigger differences of duration values.The reason may be that Chinese syllables have equal duration and learners‘ duration of English fricatives is influenced by Chinese language system.By observing the spectrograms and waveforms and analyzing the acoustic features of each fricative,the author classified three types of production errors: omission,epenthesis and substitution.Among them,substitution is the most common errors for Northeastern English learners.One reason is that there is a big difference between Chinese and English language system and EFL learners are not used to the English pronunciation habits.Moreover,one typical feature of Northeastern dialect is the confusion of flat and retroflex speech sounds,for example /ts,ts?,s/ and /t?,t?,?/.It will transfer to learners‘ English learning process.The epenthesis is caused by the different rules of syllables between Chinese and English.Most Chinese syllables end with a vowel sound and only consonants /n/ and /?/ can be the coda of one syllable.Many Northeastern English learners are not used to ending a syllable with consonant and would unconsciously add a vowel sound after the consonant.As for the reason of omission,according to ?least effort principle?,Northeastern English learners may use the least effort to pronounce the English fricatives so that some fricatives are omitted.Another reason is that most Chinese syllables end with a vowel sound instead of a consonant,so besides the epenthesis,English learners may omit the fricative in a syllable.The results of this research are significant to second language acquisition.English teachers or educators should pay attention to the differences of language systems between English and Chinese and know the negative transfer from the mother language to the second language.And they should make correct learning strategies and help students to prevent the negative transfer from the mother tongue to their English pronunciation.Students should learn some phonetic knowledge,and imitate the native speakers‘ pronunciation actively.Moreover,the voice analysis instruments,such as Praat,Minispeechlab,can be used to analyze English learners‘ speech sounds and solve their pronunciation problems.