Acknowledgements My deepest gratitude goes first and foremost to Professor aaa ， my supervisor， for her constant encouragement and She has walked me through all the stages of the writing of this Without her consistent and illuminating instruction， this thesis could not have reached its present Second， I would like to express my heartfelt gratitude to Professor aaa， who led me into the world of I am also greatly indebted to the professors and teachers at the Department of English: Professor dddd， Professor ssss， who have instructed and helped me a lot in the past two Last my thanks would go to my beloved family for their loving considerations and great confidence in me all through these I also owe my sincere gratitude to my friends and my fellow classmates who gave me their help and time in listening to me and helping me work out my problems during the difficult course of the
