| List of Abbreviations | 第1-5页 |
| List of Tables and Figures | 第5-6页 |
| Table of Contents | 第6-8页 |
| Abstract | 第8-10页 |
| 摘要 | 第10-12页 |
| Chapter One Introduction | 第12-15页 |
| ·Research Background | 第12页 |
| ·Research Purpose | 第12-13页 |
| ·Research Significance | 第13页 |
| ·Overall Organization of the Thesis | 第13-15页 |
| Chapter Two Literature Review | 第15-31页 |
| ·Mediation | 第15-18页 |
| ·The Definition of Mediation | 第15-16页 |
| ·The Classification of Mediation | 第16-18页 |
| ·The Significance of Mediation | 第18页 |
| ·Activity Theory | 第18-21页 |
| ·The Roots and Definition of Activity Theory | 第18-19页 |
| ·The Key Terms in Activity Theory | 第19-20页 |
| ·The Implications of Activity Theory on Education | 第20-21页 |
| ·The Relationship between Mediation and Activity Theory | 第21-26页 |
| ·Mediaiton in Activity Theory | 第21-22页 |
| ·Activity Theory Based on Mediation | 第22-26页 |
| ·Previous Studies | 第26-30页 |
| ·SLA from the Perspective of Mediation | 第26-27页 |
| ·SLA from the Perspective of Activity Theory | 第27-29页 |
| ·Writing from the Perspective of Activity Theory | 第29-30页 |
| ·Writing from the Perspective of Mediation in Activity theory | 第30页 |
| ·Summary | 第30-31页 |
| Chapter Three Methodology | 第31-35页 |
| ·Research Questions | 第31页 |
| ·Subjects | 第31页 |
| ·Research Context and Procedures | 第31-32页 |
| ·Instruments | 第32-33页 |
| ·Data Collection and Analysis | 第33-35页 |
| Chapter Four Results | 第35-54页 |
| ·The Network-based Writing Activity System | 第35-36页 |
| ·Mediation in the Network-based Writing Activity System | 第36-49页 |
| ·Material tools | 第37-38页 |
| ·Psychological Tools | 第38-40页 |
| ·The Human Mediators: Teacher Mediation | 第40-45页 |
| ·Teacher’s Mediation via Guides and Lectures | 第42-43页 |
| ·Teacher’s Mediation via Teaching Method | 第43-44页 |
| ·Teacher’s Mediation via Tasks | 第44页 |
| ·Teacher’s Mediation via Feedback | 第44-45页 |
| ·The Human Mediators: Peer Mediation | 第45-49页 |
| ·Peer Mediaiton through Peer Review | 第46-48页 |
| ·Peer Mediation through Peer Communities | 第48-49页 |
| ·Outcomes in the Network-based Writing Activity System | 第49-54页 |
| ·Outcomes in Cognitive Domains | 第50-52页 |
| ·Outcomes in Cognitive Knowledge | 第50-51页 |
| ·Outcomes in Cognitive Ability | 第51-52页 |
| ·Outcomes in Affective Domains | 第52页 |
| ·Outcomes in the Understanding of Meaning of Life | 第52-54页 |
| Chapter Five Discussion | 第54-58页 |
| ·Activity System A Useful Framework for Analyzing Foreign Lanugage Teaching Activity | 第54-55页 |
| ·More Abundant Mediations in the Network-based Environment | 第55-56页 |
| ·Diverse Outcomes Influenced by Various Mediatons | 第56-58页 |
| Chapter Six Conclusions and Implications | 第58-62页 |
| ·Summary of Major Findings | 第58-59页 |
| ·Implications for EFL/ESL Teaching | 第59-60页 |
| ·Limitations of the Research | 第60-61页 |
| ·Suggestions for Future Research | 第61-62页 |
| Bibliography | 第62-69页 |
| Appendix | 第69-71页 |
| Acknowledgements | 第71-72页 |
| Publication | 第72页 |
