Acknowledgments:

　　First and foremost, I would like to express my heartfelt gratitude to mysupervisor, Professor Jia Aiwu. I have benefited tremendously from her criticalthinking and insightful viewpoint. Through his patient instruction,I finally focusedon the object studied in this thesis, and obtained valuable advice on aspects rangingfrom frame work constructing and data collection to elaborated analysis.

　　Secondly, I'm profusely grateful to my respected predecessors and teachers.

　　Without their precious suggestions, I could not have come this far in this thesis.

　　Moreover, I owe my thanks to my family and friends, who have always supportedme with their generous encouragements and praises.

　　Last but not least, I sincerely thank my fellow classmates. We share joys andanxieties, which propels us forward together throughout the arduous journey.

　　Acknowledgments:

　　I would like to take this opportunity to express my sincere gratitude to the teachers,classmates and family for their kind and generqus guidance, advice,supervision and allkinds of help throughout the process of accomplishing this thesis and the wholepost-graduation period.

　　My sincere gratitude first and foremost goes to my supervisor Wang Lei, who hasgiven me thought-provoking suggestions, carefully examined my draft and madenecessary corrections. She is harsh to us under academic situations but very much like akind mother when meeting us every time, which makes me such a lucky student.

　　Without her patient guidance, my paper would never be completed.

　　I am also greatly indebted to all the teachers who have taught me in the two and ahalf year postgraduation study, especially to professor Chai Gaiying,professor SongHongbo,Professor Chen Mingyao and Professor Jia Aiwu. Their rigorous research styleand profound knowledge have impressed me a lot.

　　My sincere gratitude would also go to my beloved family,who has given metremendous support and love. Without my mother and father I would never haveachieved so much.

　　I am also owe my sincere gratitude to my fellow classmates who have given metheir help and time in listening to my complaint and helping me work out my problemswhenever I run into trouble.

　　Acknowledgments:

　　This thesis could not have been accomplished without a great deal of help frommy supervisor, my teachers, friends and family members.

　　First of all, my sincere thanks go to my supervisor who has offered me valuablesuggestions and kept patience for me for a long time.

　　Secondly, I would like to thank all the staff at the School of Foreign Languageswho has taught me in the past two and a half years. During my graduate study, I havebroadened my mind and expanded my horizon as well as shaped a much careful,critical and practical attitude,which is especially important in research.

　　Finally, I would like to extend my thanks to friends, classmates as well as myfamily members who have supported me at every stage of the writing of this thesis.

　　Acknowledgments:

　　When this experiential and intellectual projects comes to its finishing point, Iwould like to extend my heartfelt gratitude to those who have helped me during theprocess of writing for their guidance, kindness and support.

　　First and foremost, I am deeply indebted to my supervisor, Professor Chai? whoread my draft with great patience and provided penetrating suggestions for revision. Ialso want to express my sincere gratitude to the professor who recommended manybooks and materials with regard to the genre theory and appraisal theory. I should thankall the teachers who have taught me in the previous two and a half year.

　　I also would like to thank my classmates,to name just a few. I have received quitea lot of suggestions and encouragements from them, especially at the time when I felj^lost and depressed in the course of writing.

　　Last but not least,my special thankfulness goes to my dear families for theirendless affection, constant understanding and support of my further study.

　　Acknowledgements:

　　This study is only a small design and research, but it receives quite a lot of help inprocess. Without those help, this study would not reach this present level. I am grateful to allthose who have helped me on this study. I would like to express my sincere gratitude to mysupervisor-professor Baibin, for his incisive advices and valuable suggestions in achievementof this study. Though there is long geographic distance between us, it did not make anytroubles. Professor Bai 's comments to my study are always to the point both on content andstructures.

　　I would also like to thank my friend Xia Shiyang who gives great help and support to meduring this time. With his cooperation I could do the research in the fourth chapter to achievethis study successfully.

　　Acknowledgements:

　　Upon the completion of this thesis, I would like to take this opportunity to express mysincere thanks to those who have assisted me a lot with my thesis and postgraduate study invarious ways. Without their help, this thesis could have never been completed.

　　First, I'd like to express my sincere gratitude to my supervisor, Associate Professor FanXiaobo, who he gave me great encouragement, insightful suggestions and continuous help.

　　He spent plenty of time enlightening me and provided different sources of information to me.

　　I appreciate his kindness and patience because he was pleased to discuss with me any time.

　　After I finished my first manuscript, he gave his feedback very quickly and corrected mymistakes very carefully. Thanks to his constant encouragement and patient guidance.

　　Moreover, his great devotion to research on linguistics and teaching has dramaticallyinfluenced me on my attitude towards future study and the whole life.

　　Besides, my special thanks are also extended to all the professors who have helped andinfluenced me and broadened my horizon during my graduate study.

　　Last but not least, I am also very grateful to my parents and classmates who gave me alot of support and encouragement from different aspects which I obtain great strength to finishmy thesis.

　　Acknowledgements:

　　I would like thank all those have helped me to make this thesis possible and better than itotherwise would have been.

　　Firstly, sincerely thank for my mentor, Zhao Bing,a respectable, responsible scholar, whoprovides her expert guidance, encouragement and suggestions throughout my MA dissertationwriting. Without her illustration and inspiration, I could hardly complete my thesis. Her keen andmeticulous academic observation enlightens me not only in this thesis but in my future study.

　　Secondly,thank for the teachers in foreign language college. Their lessons and behaviorinfluent me greatly, changing my old idea about studying and teaching English. Second LanguageAcquisition teaches me how study happens,the process of studying language and how to get betterresult by studying. These have enriched my theoretical knowledge.

　　Thirdly, thank for my students of Northwest University for Nationalities. Without theirparticipation and cooperation, the present thesis is impossible.

　　Last but not least, thank for my parents and husband-for their endless love and support. Withtheir encouragement and concern, I can finish the thesis writing.