An Acoustic Study On Affricates Produced By Harbin English Learners

An ever-growing attention has been paid to spoken English in the process of English teaching.In order to improve learners' pronunciation,we should attach importance to the production of consonants,for if a consonant in a syllable is not properly produced,a foreign accent might be caused,which would further lead to misunderstanding,reducing the efficacy of communication.Deviant production of consonants widely exists in second or foreign language learners no matter what mother tongue they speak.To solve this problem,previous scholars have conducted relevant research from various aspects.But up to now,there are few studies on the acquisition of L2 affricates.In addition,the influence of dialects on the acquisition of L2 affricates has not been fully discussed,which,to some extent,reduces the effect of English pronunciation teaching.Therefore,this thesis aims to study,from the perspective of acoustic phonetics,the production of English affricates by learners from Harbin dialect region,so as to find out the problems in their pronunciation.The following three questions are going to be answered in the thesis:1)What are the features of affricates produced by Harbin English learners? What are the differences between their production and that of American English speakers?2)What are the possible reasons for the differences?3)How effective are the two theories,Transfer Theory and Speech Learning Model,in predicting the mother tongue influence on learners' acquisition of English affricates?The corpus AESOP-CASS was adopted in this research,from which the sound samples were collected,and among them,words with English affricates produced by16 American English speakers(7 females and 9 males)and 50 Harbin English learners(25 females and 25 males)were taken as the research objects,which were further annotated by the acoustic phonetics software Praat 4.6.On this basis,the required parameter values were extracted.Two parameters are extracted,namely,voice onset time(VOT),able to reflect the voicing and aspiration status of affricates,and GAP,the indicator of the articulation tension.By using these two parameters,a spatial acoustic pattern was established for the purpose of analyzing and comparing the distribution of English affricates produced by Harbin learners and native speakers.In addition,to quantify the production features of the learners,independent sample T-test was conducted on the collected data of the above two parameters,and those of another parameter,duration of friction(DOF),through which whether learners' production is significantly different from the native speakers can be proved.Besides,the places of articulation of learners and speakers were also compared by measuring another parameter,amplitude,whose variation is correlated with the backness of the articulator.The sound samples in the two participant groups,whose DOF is closest to the group mean values,were taken as the representative samples,and the manifestations of amplitude on waveform and spectrogram were compared so as to show the differences in articulation place of the two groups.Meanwhile,this research also extracted relevant parameter values of Harbin dialect affricates,which were adopted to explore the influence of learners' mother tongue on the acquisition of English affricates.Relevant data of Mandarin Chinese was cited from previous experiments.In order to explain the differences in affricate pronunciation between learners and native speakers,transfer theory and speech learning model are employed in this research to do the explanation.Based on the T-test of English and Harbin dialect affricate production in terms of the investigated parameter values,and by integrating the results with the acquisition performance of the learners,the influence of learners' mother tongue was revealed,which was further analyzed by interlanguage theory.It is discovered from this research that segments produced by Harbin English learners are distributed in a more disperse way compared with those of the native speakers.In addition,the highest point of their tongue is also more back or advanced than their native counterparts.Besides,learners tend to omit the plosion before release.Their articulator tension and DOF are different from those the native speakers.Some of the learners even cannot distinguish affricates from fricatives or plosives.However,both voicing and aspiration status of English affricates are well acquired by learners.As for the transferring effect imposed by learners' mother tongue on their acquisition,it is noticed that both the differences and similarities between learners' L1 and L2 will to a certain extent impede or facilitate learners' L2 acquisition.Other non-linguistic factors,such as learners' age starting to learn the target language,motivation,learning environment,etc.will bring certain influence on their acquisition.The above findings further prove that both transfer theory and SLM are partly workable in the prediction of the aforementioned influence,yet neither of them alone can explain the phenomena investigated in the research.In conclusion,findings of this research can help English teachers to have more knowledge of the affricate production features of Harbin English learners,and help them to accurately locate the deviations which occur in Harbin learners' production and have them effectively corrected,thus improving English teaching.Additionally,the results concluded in this research will also be helpful to the enhancement of sound composition and synthesis.From the theoretical perspective,the validity of transfer theory and speech learning model in the explanation of L2 English affricate acquisition can be verified.