| Acknowledgements | 第1-5页 |
| Abstract | 第5-7页 |
| 摘要 | 第7-13页 |
| Chapter One Introduction | 第13-18页 |
| ·Background of the study | 第13-15页 |
| ·Purpose and significance of the study | 第15-16页 |
| ·Layout of the thesis | 第16-18页 |
| Chapter Two Literature Review | 第18-34页 |
| ·Definition of lexical chunks | 第18-20页 |
| ·Classification of lexical chunks | 第20-26页 |
| ·Nattinger & DeCarrico's classification | 第20-22页 |
| ·Lewis' classification | 第22-23页 |
| ·Biber et al.'s classification | 第23-24页 |
| ·The working classification and criteria | 第24-26页 |
| ·Previous studies on lexical chunks | 第26-31页 |
| ·Studies on lexical chunks abroad | 第26-29页 |
| ·Studies on lexical chunks in China | 第29-31页 |
| ·The role of lexical chunks in language acquisition | 第31-34页 |
| Chapter Three Research Design and Methodology | 第34-39页 |
| ·Research questions | 第34-35页 |
| ·Corpus used and the selection of samples | 第35-37页 |
| ·Data collection | 第37-39页 |
| Chapter Four Results and Discussion | 第39-50页 |
| ·Results | 第39-45页 |
| ·Comparison of lexical chunks used in the two groups | 第39-43页 |
| ·Correlation between lexical chunks and composition scores | 第43-45页 |
| ·Discussion | 第45-50页 |
| ·A comparison of lexical chunks used between high-mark compositions and low-mark compositions | 第45-48页 |
| ·Relationship between lexical chunks using and English writing proficiency | 第48-50页 |
| Chapter Five Conclusion | 第50-54页 |
| ·Major findings of the present study | 第50-51页 |
| ·Some pedagogical implications | 第51-52页 |
| ·Limitations of the present study | 第52-54页 |
| References | 第54-57页 |
| Appendix | 第57-58页 |
| Publications | 第58页 |
