| Acknowledgements | 第1-6页 |
| 内容摘要 | 第6-8页 |
| Abstract | 第8-13页 |
| 1. Introduction | 第13-17页 |
| ·Research background | 第13-14页 |
| ·Objective and significance of the study | 第14-15页 |
| ·Structure of the thesis | 第15-17页 |
| 2. Literature Review and Theoretical Framework | 第17-28页 |
| ·literature review | 第17-24页 |
| ·Definition of code switching | 第17-18页 |
| ·Classifications of code switching | 第18-19页 |
| ·Approaches to the analysis of code switching | 第19-24页 |
| ·The sociolinguistic approach | 第19-20页 |
| ·The grammatical approach | 第20-22页 |
| ·The psycholinguistic approach | 第22页 |
| ·The conversational analysis approach | 第22-23页 |
| ·The pragmatic approach | 第23-24页 |
| ·Theoretical framework | 第24-28页 |
| 3. Research Methodology | 第28-33页 |
| ·Research questions | 第28页 |
| ·Subjects | 第28-30页 |
| ·Data collection | 第30-33页 |
| ·Tape recording and data transcription | 第30-31页 |
| ·Observation | 第31页 |
| ·Questionnaire survey and interview | 第31-33页 |
| 4. Findings and Discussion | 第33-50页 |
| ·Findings concerning teachers | 第33-41页 |
| ·Frequency of teachers' code switching and influence factors | 第33-34页 |
| ·Types of code switching used by teachers and functional analysis | 第34-38页 |
| ·General description of teachers' code switching concerning main courses | 第38-39页 |
| ·Teachers' attitudes towards code switching | 第39页 |
| ·Degree of teachers' consciousness towards code switching | 第39-40页 |
| ·Reasons of teachers conducting code switching | 第40-41页 |
| ·Findings concerning students | 第41-43页 |
| ·Students' attitudes towards teachers' code switching | 第41-42页 |
| ·Impact of teachers' code switching on students' English learning | 第42-43页 |
| ·Reasons of teachers' code switching from pragmatic adaptatiton perspective | 第43-50页 |
| ·Code switching as adaptation to the linguistic reality | 第43-45页 |
| ·Code switching as adaptation to the social conventions | 第45页 |
| ·Code switching as adaptation to teacher's roles | 第45-48页 |
| ·Code switching as adaptation to the psychological motivations | 第48-50页 |
| 5. Conclusion | 第50-53页 |
| ·Major findings | 第50-51页 |
| ·Pedagogical implication | 第51-52页 |
| ·Limitations of the study and suggestions for future research | 第52-53页 |
| Bibliography | 第53-56页 |
| Appendix Ⅰ | 第56-57页 |
| Appendix Ⅱ | 第57-59页 |
| Appendix Ⅲ | 第59页 |
