| ACKNOWLEDGEMENTS | 第5-6页 |
| 摘要 | 第6-8页 |
| ABSTRACT | 第8-9页 |
| CHAPTER Ⅰ INTRODUCTION | 第14-17页 |
| 1.1 Research Background | 第14-15页 |
| 1.2 Purpose of the Present Study | 第15页 |
| 1.3 Significance of the Present Study | 第15页 |
| 1.4 Overall Structure of the Thesis | 第15-17页 |
| CHAPTER Ⅱ LITERATURE REVIEW | 第17-33页 |
| 2.1 Theoretical Backgrounds | 第17-25页 |
| 2.1.1 Language Aptitude | 第17-23页 |
| 2.1.1.1 Definitions of Language Aptitude | 第17-18页 |
| 2.1.1.2 Nature of Language Aptitude | 第18-20页 |
| 2.1.1.3 Measurement of Language Aptitude | 第20-22页 |
| 2.1.1.4 Components of Language Aptitude | 第22-23页 |
| 2.1.2 Third Language Acquisition/Multilingualism | 第23-24页 |
| 2.1.3 Metalinguistic Awareness | 第24页 |
| 2.1.4 Perceived Positive Language Interaction | 第24-25页 |
| 2.2 Previous Studies on the Relationship among Multilingualism, MetalinguisticAwareness and Language Aptitude | 第25-30页 |
| 2.2.1 Relationship between Multilingualism and Metalinguistic Awareness | 第25-26页 |
| 2.2.2 Relationship between Metalinguistic Awareness and Language Aptitude | 第26-27页 |
| 2.2.3 Relationship between Multilingualism and Language Aptitude | 第27-30页 |
| 2.3 Comments on Problems in the Existing Studies and Solutions in the PresentStudy | 第30-33页 |
| CHAPTER Ⅲ METHODOLOGY | 第33-41页 |
| 3.1 Research Questions and Hypotheses | 第33-34页 |
| 3.2 Participants | 第34页 |
| 3.3 Instruments | 第34-39页 |
| 3.3.1 The LLAMA Aptitude Test | 第34-37页 |
| 3.3.2 Perceived Positive Language Interaction Questionnaire | 第37-39页 |
| 3.3.2.1 Pilot Study | 第37-38页 |
| 3.3.2.2 Internal Consistency within Subscales of PPLI | 第38-39页 |
| 3.4 Procedures of Data Collection | 第39-40页 |
| 3.5 Data Analysis | 第40-41页 |
| CHAPTER Ⅳ RESULTS | 第41-48页 |
| 4.1 Results of the LLAMA Aptitude Test | 第41-45页 |
| 4.1.1 Descriptive Statistics of Language Aptitude | 第41-42页 |
| 4.1.2 Comparison of Language Aptitude between L2 and L3 Learners | 第42-44页 |
| 4.1.3 Comparison of Language Aptitude between Learners of Different L3s | 第44-45页 |
| 4.2 Results of the Perceived Positive Language Interaction Questionnaire | 第45-48页 |
| 4.2.1 Descriptive Statistics of PPLI | 第45-46页 |
| 4.2.2 Comparison of PPLI between Learners of Different L3s | 第46页 |
| 4.2.3 Correlation between Language Aptitude and PPLI | 第46-48页 |
| CHAPTER Ⅴ DISCUSSION | 第48-57页 |
| 5.1 Differences in Language Aptitude between L2 and L3 Learners | 第48-51页 |
| 5.2 Differences in Language Aptitude between Learners of Different L3s | 第51-52页 |
| 5.3 Differences in Perceived Positive Language Interaction between Learners ofDifferent L3s | 第52-55页 |
| 5.4 Relationship between Language Aptitude and Perceived Positive LanguageInteraction | 第55-57页 |
| CHAPTER Ⅵ CONCLUSION | 第57-60页 |
| 6.1 Major Findings of the Study | 第57-58页 |
| 6.2 Theoretical and Pedagogical Implications | 第58-59页 |
| 6.3 Limitations and Suggestions for Future Research | 第59-60页 |
| REFERENCES | 第60-68页 |
| APPENDIX A: LLAMA APTITUDE TEST | 第68-70页 |
| APPENDIX B: PERCEIVED POSITIVE LANGUAGE INTERACTIONQUESTIONNAIRE | 第70-71页 |
| APPENDIX C: 攻读硕士学位期间发表论文 | 第71页 |
