| Acknowledgments | 第1-6页 |
| Abstract | 第6-8页 |
| 中文摘要 | 第8-11页 |
| Chapter One Introduction | 第11-14页 |
| ·Study Background | 第11-12页 |
| ·Significance and Purpose of the Study | 第12页 |
| ·Layout of the Thesis | 第12-14页 |
| Chapter Two Literature Review | 第14-25页 |
| ·Study of Hedges from Semantic Perspective | 第14-16页 |
| ·Study of Hedges from Pragmatic Perspective | 第16-19页 |
| ·Study of Hedges from Cognitive Perspective | 第19-21页 |
| ·Study of Hedges from Systemic-functional Perspective | 第21-22页 |
| ·Studies of Classroom Discourses | 第22-25页 |
| Chapter Three Research Methodology | 第25-27页 |
| ·Research Questions | 第25页 |
| ·Data Collection | 第25页 |
| ·Research Procedures | 第25-27页 |
| Chapter Four Results and Analysis | 第27-37页 |
| ·General Picture of Hedges Used in Classroom Discourses | 第27-33页 |
| ·Overall Frequency of Hedges | 第27-29页 |
| ·Adaptors in Classroom Discourses | 第29-30页 |
| ·Rounders in Classroom Discourses | 第30页 |
| ·Plausibility Shields in Classroom Discourse | 第30-32页 |
| ·Attribution Shields in Classroom Discourses | 第32-33页 |
| ·Analysis of Hedges employed in Classroom Discourses | 第33-37页 |
| ·Analysis of Hedges on the Basis of Cooperative Principle | 第33-35页 |
| ·Analysis of Hedges according to Politeness Principle | 第35-37页 |
| Chapter Five Pragmatic Functions of Hedges | 第37-40页 |
| ·Filling Lexical Gaps | 第37-38页 |
| ·Reduction of the “Affective Filter” | 第38-39页 |
| ·Creating a Mild Tone | 第39页 |
| ·Self-Protection | 第39-40页 |
| Chapter Six Conclusion | 第40-44页 |
| ·Major Findings | 第40-41页 |
| ·Pedagogical Implications | 第41-42页 |
| ·From the Angle of Teachers | 第41-42页 |
| ·From the Angle of students | 第42页 |
| ·Some Suggestions for Teaching Hedges | 第42页 |
| ·Research limitations | 第42-43页 |
| ·Suggestions for Further Study | 第43-44页 |
| Reference | 第44-48页 |
| Appendix I Examples Cited in the Thesis | 第48-52页 |
