(1)myheartfeltthanks go tomy tutor, professorx,who has helped me in the completion of this thesis in mi measurableways. he read my draftswith incredible strictness and carefulness, and his suggestions and commentshave been encouraging, rigorous, critical and discerning.w ithout his enlightening suggestions and great encouragemen,t itwould not be possible for this thesis to achieve itspresent end. i amespeciallygrateful to hmi for his graciousand earnest assistance and guidance throughoutmy threeyear studies.

(2) iwish to thankmy profound and respectable academic advisor, professorx, for his valuable instruction inthe field ofapplied linguistics andhisgreatpatience in thepast threeyears.i’m also grateful to hmi forhis suggestionsandencouragementand all the efforts he hasmade to helpme complete the paper.

(3) my special thanks go to x and all the studentsfrom cdut who have participated in my research for theirinvaluable contribution tomy data collection, andx forprovidingmewith the result of statistical analyses of the data,and above all tomy family for their support and encouragementduring the course of the accomplishmentof this thesis.

(4)many professors, friends and colleagueshave contributed tomy thesismore or less directly...

(5) thanks also go to the pla foreign languageuniversitywhose financial assistance enabled me to furthermydoctoral research in beijing university and in the department of comparative literature in the state university ofnewyork atbuffalo.

(6) firstofal,l iwould liketo acknowledgemy supervisor, professor zhang yang, who offered insightful andpowerful suggestionson mi provingmy thesis, andwhose lectureswere ofgreathelp and value inmy thesiswriting.

(7) imustextendmy thanks tohuangl,i my belovedwife, forherendless supportand encouragement; tomyparents-in-law for their baby-sittingmy lovely daughter,which savesme a lotof tmi e and energy for the thesis.