| Acknowledgements | 第1-11页 |
| Abstract | 第11-13页 |
| 中文摘要 | 第13-15页 |
| Chapter 1 Introduction | 第15-19页 |
| ·Background of the Study | 第15-17页 |
| ·Significance of the Study | 第17-18页 |
| ·Organization of the Thesis | 第18-19页 |
| Chapter 2 Literature Review | 第19-38页 |
| ·Concepts of Lexical Chunks | 第19-22页 |
| ·Definitions | 第19-21页 |
| ·Classifications | 第21-22页 |
| ·Relevant Theories of the Study | 第22-25页 |
| ·Dual System of Language | 第22-24页 |
| ·Functions of Lexical Chunks in SLA | 第24-25页 |
| ·Lexical Chunks in First Language Acquisition | 第25-28页 |
| ·Patterns of Lexical Chunks in Child Language | 第25-27页 |
| ·Lexical Chunks in the First Language Acquisition Process | 第27-28页 |
| ·Lexical Chunks in SLA | 第28-30页 |
| ·Patterns of Lexical Chunks in SLA | 第29页 |
| ·Lexical Chunks in SLA Process | 第29-30页 |
| ·Empirical Studies on Lexical Chunks at Home and Abroad | 第30-36页 |
| ·Empirical Studies Abroad | 第30-32页 |
| ·Empirical Studies at Home | 第32-36页 |
| ·Limitations of Previous Empirical Researches | 第36-38页 |
| Chapter 3 Methodology | 第38-46页 |
| ·Writing Materials | 第38页 |
| ·Research Questions | 第38-39页 |
| ·Data Collection | 第39-44页 |
| ·Procedure of Collecting Students' Writings | 第39-40页 |
| ·Criterion of Identification of Lexical Chunks | 第40页 |
| ·Criterion for Classification of Lexical Chunks | 第40-42页 |
| ·Samples of Identificaion and Classification of the Study | 第42-44页 |
| ·Data Analysis | 第44-46页 |
| ·Methods of Data Analysis | 第44页 |
| ·Procedure of Data Analysis | 第44-46页 |
| Chapter 4 Results and Discussion | 第46-70页 |
| ·General Characteristics of Using Lexical Chunks | 第46-53页 |
| ·Three Factors of Lexical Chunks | 第46-47页 |
| ·Frequency of Lexical Chunks | 第47-48页 |
| ·Variety of Lexical Chunks | 第48-49页 |
| ·Four Types of Lexical Chunks | 第49-50页 |
| ·Typical Errors in Using lexical Chunks | 第50-53页 |
| ·Relationships Between the Use of Lexical Chunks and Writing Scores | 第53-56页 |
| ·Differences in Using Lexical Chunks Between High and low Scorers | 第56-63页 |
| ·Difference in Three Factors of Lexical Chunks | 第56-58页 |
| ·Difference in the Frequency and the Variety of Lexical Chunks | 第58-60页 |
| ·Difference in the Distribution of Lexical Chunks | 第60-63页 |
| ·Difference in Using of Lexical Chunks Between Sophomores' and Juniors'Compositions | 第63-70页 |
| ·Difference in Three Factors of Lexical Chunks | 第63-65页 |
| ·Difference in the Frequency and the Variety of Lexical Chunks | 第65-67页 |
| ·Difference in the Distribution of Lexical Chunks | 第67-70页 |
| Chapter 5 Conclusions | 第70-74页 |
| ·Major Findings | 第70-71页 |
| ·Pedagogical Implications | 第71-72页 |
| ·Limitations and Suggestions for Further Studies | 第72-74页 |
| Bibliography | 第74-77页 |
| Appendix Ⅰ | 第77-78页 |
| Appendix Ⅱ | 第78-80页 |
| Appendix Ⅲ | 第80-83页 |
