| Abstract | 第4-5页 |
| 摘要 | 第6-9页 |
| Chapter One Introduction | 第9-15页 |
| 1.1 Background of the Research | 第9-10页 |
| 1.2 Significance of the Research | 第10-13页 |
| 1.3 Research Questions | 第13-14页 |
| 1.4 Organization of the Thesis | 第14-15页 |
| Chapter Two Literature Review | 第15-26页 |
| 2.1 Language as Cognitive Mediator | 第15-18页 |
| 2.2 Mental Activities Mediated by Native Language and Culture | 第18-20页 |
| 2.3 Incapability of Second Language as Cognitive Mediator | 第20-26页 |
| Chapter Three Research Design | 第26-32页 |
| 3.1 Subjects | 第27-28页 |
| 3.2 Instrument Design | 第28-30页 |
| 3.3 Data Collection | 第30-32页 |
| Chapter Four Results and Discussions | 第32-56页 |
| 4.1 Social Condition of Education in Tibetan Regions | 第32-34页 |
| 4.2 Language Environment and Choice of Language Mediator | 第34-38页 |
| 4.3 Students’ Capability of Code-switching between Languages | 第38-41页 |
| 4.4 Initiate Age of Students to Communicate in Chinese | 第41-44页 |
| 4.5 Students’ Academic Achievements | 第44-46页 |
| 4.6 Tibetan as Mediator in Curriculum and Instruction | 第46-49页 |
| 4.7 Chinese as Mediator in Curriculum and Instruction | 第49-52页 |
| 4.8 Tibetan Students’ Needs on Language Mediator | 第52-53页 |
| 4.9 Summary | 第53-56页 |
| Chapter Five Conclusion | 第56-65页 |
| 5.1 Major Findings | 第56-60页 |
| 5.2 Implications | 第60-65页 |
| Acknowledgements | 第65-66页 |
| Bibliography | 第66-69页 |
| Appendix Ⅰ | 第69-73页 |
| Appendix Ⅱ | 第73-77页 |
| Publication | 第77-78页 |
