The accomplishment of this thesis has covered half a year,s experiment and another halfa year's analysis. It can not be denied that whole process is quite tough. Despite all theproblems during research and limitations, the thesis finally comes into being. However, thiscan not be achieved without the help of many people.
First and foremost, I would like to give my sincere gratitude to my distinguished andrespectable supervisor, Prof. Qi Yuanfang, for his all-along supports during not only theresearch process, but the whole post-graduate year. He is the one who gives me inspiration ofthe thesis topic, enlightens me empirical method helps me conduct teaching experiment, andinstructs me analyzing approaches. I have to say that this thesis is born from his insightfulinstructions and warm encouragement.
Secondly, I also own my appreciation to Prof, Gongrong who gives me a lot ofinspiration, insightful advice and instructions.
And also, this thesis can not be accomplished without teachers of Foreign LanguagesSchool who impart knowledge to me and classmates who offer me help.
Last but not least, I would like to extend my thanks to the students participating in thisresearch for their patient corporation.