| Abstract | 第4页 |
| Acknowledgement | 第5-8页 |
| List of Tables | 第8-9页 |
| List of Figures | 第9-10页 |
| Chapter 1 Introduction | 第10-13页 |
| 1.1 Statement of the Problem | 第10-11页 |
| 1.2 Research Questions and Hypotheses | 第11-12页 |
| 1.3 Overview of the Content | 第12-13页 |
| Chapter 2 Theoretical Rationale and Literature Review | 第13-24页 |
| 2.1 Theoretical Rationale | 第13-22页 |
| 2.1.1 The Interaction Hypothesis | 第13-14页 |
| 2.1.2 Vygotsky’s Concept of the Zone of Proximal Development | 第14-19页 |
| 2.1.2.1 Utilitarian Approach to Vygotsky’s Concept | 第14-19页 |
| 2.1.2.1.1 Vision of the ZPD: Learning Through Scaffolding | 第15-17页 |
| 2.1.2.1.2 Focusing on the Mediums of Learning | 第17页 |
| 2.1.2.1.3 ZPD for Study and Change in Education | 第17-18页 |
| 2.1.2.1.4 Significance | 第18-19页 |
| 2.1.3 Scaffolding | 第19-20页 |
| 2.1.4 Patterns of Interaction | 第20-22页 |
| 2.2 Literature Review | 第22-24页 |
| 2.2.1 Effect of Partners’Proficiency Levels | 第22-23页 |
| 2.2.2 Patterns of Pair Interaction | 第23-24页 |
| Chapter 3 The Present Study | 第24-28页 |
| 3.1 Subjects | 第24-25页 |
| 3.2 Procedures and Materials | 第25-26页 |
| 3.3 Data Analysis | 第26-28页 |
| 3.3.1 The Topics and Criteria | 第26页 |
| 3.3.2 Interrater Reliability | 第26页 |
| 3.3.3 Scores | 第26页 |
| 3.3.4 Fluency, Amount and Diversity | 第26-27页 |
| 3.3.5 Patterns of Pair Interaction | 第27-28页 |
| Chapter 4 Results and Discussion | 第28-44页 |
| 4.1 Question 1: Do partners’proficiency levels affect test-takers’scores received? | 第28-30页 |
| 4.2 Question 2: Do partners’proficiency levels have an impact on test-takers’fluency of the language produced | 第30-32页 |
| 4.3 Question 3: Are the repairs associated with the scores received? | 第32-33页 |
| 4.4 Question 4: Do partners’proficiency levels have an impact on test-takers’amount of the language produced? | 第33-35页 |
| 4.5 Question 5: Is the amount of language produced associated with the scores received? | 第35-36页 |
| 4.6 Question 6: Do partners’proficiency levels have an impact on test-takers’D-optimum average produced? | 第36-38页 |
| 4.7 Question 7: Is the D-optimum average produced associated with the scores received? | 第38-39页 |
| 4.8 Question 8: Are the partners’proficiency levels associated with the patterns of interaction produced in the paired tasks? | 第39-44页 |
| Chapter 5 Conclusion | 第44-46页 |
| 5.1 Summary of the Study | 第44-45页 |
| 5.2 Implications and Limitations of the Study | 第45-46页 |
| References | 第46-50页 |
| Appendix I Oral Topics Adopted in the Whole Process of the Assessment | 第50-51页 |
| Appendix II Scoring Criteria Adopted in This Study: CET Spoken English Test | 第51页 |
