AcknowledgementsI would like to express my gratitude to all those who have helped me during the writing of this thesis
I gratefully acknowledge the help of my supervisor, Mr
Liu Zhigang, who has offered me valuable suggestions in the academic studies
In the preparation of the thesis, he has spent much time reading through each draft and provided me with inspiring advice
Without his patient instruction, insightful criticism and expert guidance, the completion of this thesis would not have been possible
I also owe a special debt of gratitude to all the professors in Foreign Languages Institute, from whose devoted teaching and enlightening lectures I have benefited a lot and prepared for the thesis academically
My heartfelt thanks also go to my parents who have constantly inspired and sup