| Acknowledgments | 第1-6页 |
| Abstract | 第6-8页 |
| 摘要 | 第8-12页 |
| List of Tables | 第12-14页 |
| List of Abbreviations | 第14-15页 |
| Chapter 1 Introduction | 第15-20页 |
| ·Objectives of the research | 第16页 |
| ·Significance of the research | 第16-17页 |
| ·Definition of subordinate interrogatives | 第17-18页 |
| ·Organization of the thesis | 第18-20页 |
| Chapter 2 Literature Review | 第20-40页 |
| ·Optimality theory (OT) | 第20-36页 |
| ·Basic working mechanism of OT | 第20-23页 |
| ·OT analysis of syntax | 第23-33页 |
| ·OT studies on language acquisition | 第33-36页 |
| ·Studies on acquisition of English WH-subordinate interrogatives | 第36-40页 |
| Chapter 3 Methodology | 第40-45页 |
| ·The participants | 第40页 |
| ·Instrument and procedure | 第40-42页 |
| ·Data collection and data analysis | 第42-45页 |
| Chapter 4 Results and Discussions | 第45-66页 |
| ·The total error rate of each grade in each sentence type of EWSI | 第45-46页 |
| ·Grade One students’ICHR in each sentence type of EWSI | 第46-53页 |
| ·Error types of Grade One students in each sentence type of EWSI | 第46-47页 |
| ·Grade One students’ICHR in Sentence Type Three | 第47-49页 |
| ·Grade One students’ICHR in Sentence Type Four | 第49-50页 |
| ·Grade One students’ICHR in Sentence Type Five | 第50页 |
| ·Grade One students’ICHR in Sentence Type Six | 第50-53页 |
| ·Grade Two students’ICHR in EWSI | 第53-58页 |
| ·Error types of Grade Two students in each sentence type of EWSI | 第53-54页 |
| ·Grade Two students’ICHR in Sentence Type Four | 第54-55页 |
| ·Grade Two students’ICHR in Sentence Type Six | 第55-58页 |
| ·Grade Three students’ICHR in each sentence type of EWSI | 第58-60页 |
| ·Error types of Grade Three students in each sentence type | 第58-59页 |
| ·Grade Three students’ICHR in each sentence type | 第59-60页 |
| ·Developmental trend of ICHR in EWSI | 第60-66页 |
| ·Second language acquisition algorithm | 第61-62页 |
| ·Characteristics of ICHR in EWSI | 第62-64页 |
| ·SLA sequence of learning EWSI sentence types | 第64-66页 |
| Chapter 5 Conclusion | 第66-70页 |
| ·Findings of the research | 第66-67页 |
| ·Implications of the research | 第67-68页 |
| ·Suggestions for further research | 第68-70页 |
| Bibliographies | 第70-75页 |
| Appendix I | 第75-77页 |
| Appendix II Published Papers during the Study of M.A | 第77页 |
