| 中文摘要 | 第1-5页 |
| Abstract | 第5-12页 |
| Chapter One Introduction | 第12-16页 |
| ·Research rationale | 第12-14页 |
| ·Significance of this study | 第14-15页 |
| ·Layout of this study | 第15-16页 |
| Chapter Two Literature review | 第16-29页 |
| ·Hedges study | 第16-23页 |
| ·Definitions of hedges | 第16-17页 |
| ·Classifications of hedges | 第17-23页 |
| ·Classifications given by linguists abroad | 第17-21页 |
| ·Classifications given by linguists at home | 第21-22页 |
| ·Perspective adopted in the present study | 第22-23页 |
| ·Abstracts study | 第23-28页 |
| ·Definitions and functions of an abstract | 第23-24页 |
| ·Related researches in abstract writing | 第24-27页 |
| ·Studies on the macro-structures of RA abstracts | 第24-25页 |
| ·Studies on the linguistic features of RA abstracts | 第25-26页 |
| ·Contrastive analysis of RA abstracts | 第26-27页 |
| ·Important role of hedges in abstract writing | 第27-28页 |
| ·Summary | 第28-29页 |
| Chapter Three Methodology | 第29-35页 |
| ·Research purposes and research questions | 第29页 |
| ·Data collection | 第29-31页 |
| ·Criteria of data collection | 第30-31页 |
| ·Data sources | 第31页 |
| ·Instruments | 第31-32页 |
| ·Data analysis and processing procedures | 第32-35页 |
| ·Approaches to identifying hedges | 第32-34页 |
| ·Processing procedures | 第34-35页 |
| Chapter Four Results and Discussions | 第35-60页 |
| ·Overview | 第35-41页 |
| ·Overall frequency and distribution of hedges in both corpus | 第36-39页 |
| ·Most-frequently-used hedges in different categories in both corpus | 第39-41页 |
| ·Different distributions and frequencies of hedges in each type | 第41-58页 |
| ·Modal auxiliaries | 第41-45页 |
| ·Epistemic adverbs | 第45-48页 |
| ·Epistemic verbs | 第48-53页 |
| ·Epistemic adjectives | 第53-56页 |
| ·Epistemic nouns | 第56-58页 |
| ·Summary | 第58-60页 |
| Chapter Five Conclusion | 第60-64页 |
| ·Major Findings | 第60-61页 |
| ·Pedagogical Implications | 第61-62页 |
| ·Raising awareness of hedges | 第61-62页 |
| ·Improving pragmatic competence | 第62页 |
| ·Limitations | 第62-63页 |
| ·Theoretical limitations | 第62-63页 |
| ·Methodological limitations | 第63页 |
| ·Suggestions for further study | 第63-64页 |
| References | 第64-70页 |
| Appendix Ⅰ:List of lexical hedges employed in the two corpus | 第70-72页 |
| Appendix Ⅱ Sample | 第72-73页 |
| Acknowledgements | 第73页 |
