An Experimental Study On Dental Stops Of Standard Chinese By American Learners

We found in teaching activity that dental stops d and t by American Chinese learners are accompanied with a tendency of affrication,which means they sound like the affricates z,c or j,q in standard Chinese.To verify this phenomenon,through pronunciation experiment,acoustical and statistical analysis,this study investigated VOT,consonant length,ratio of affrication to aspiration of Chinese dental stops d and t by 10 American learners with intermediate level of standard Chinese,and compared them with dental stops d,t and corresponding affricates z,c or c,q by 6 native speakers,so as to investigate whether they had a tendency of affrication.The specific results and conclusions reached are as follows:First,the VOT and the consonant length of the American learner's stop d are longer than those of the corresponding parameters of the Chinese native speaker's stop d,and are approaching to those of the native speakers' affricate z/j.The VOT of the stop t by American learners is shorter than that of the Chinese native speakers' t,and the consonant length is not different from that of the native speakers.As a result,on VOT and consonant length,only stop d by American learners have shown the affrication tendency.Second,the ratios of affrication within the stops d and t by the American learners account for about two-fifths of the total length of the stops,which are larger than the affrication ratio of the stops d and t by the Chinese native speakers,and are smaller than the that of the affricate z/j and c/q.This shows that the timbre of affrication,which lasts for quite some time inside the stops,is one of the reasons for the tendency of the Chinese dental stops produced by American learners.Third,to combine the first two points,dental stops by American learners are accompanied with a tendency of affrication to some extent.The VOT,the length of consonant and the ratio of affrication and aspiration can prove the tendency in d,while only the ratio can prove the tendency in t.Forth,the number of phonemes and tongue position of the vowels will affect the extent of affrication of the initials by Chinese and American speakers,but in general,the influence that the American learners got are more comprehensive,systematic and regular than that on native speakers of Chinese.This phenomenon is due to learners' incorrect place of articulatory gestures and manners of articulation.This study not only compared dental stops by American learners with the same stops by native Chinese speakers,but also compared them with the affricates by native speakers;not only examined the VOT and the consonant length of the initials,but also examined the internal structure of the initials.These constitute the main characteristics of this study.