给你我的吧..不过我是把三份范文结合起来的.. First and foremost, I appreciate my country who give me a comfortable learning atmosphere. Second, I would like to show my deepest gratitude to my supervisor, Prof. Li Yuexiang, who has walked me through all the stages of the writing of this thesis. Without her illuminating instruction and patience, this thesis could not have reached its present form. I am also greatly indebted to all my teachers who have helped me to develop the fundamental and essential academic competence. My sincere appreciation also goes to all my classmates, who are my proud of my life. Last but not least, I want to thank all my friends, especially my three lovely roommates, for their encouragement and support.。