| Acknowledgements | 第1-4页 |
| Abstract in Chinese | 第4-6页 |
| Abstract in English | 第6-9页 |
| Ⅰ． A Brief Account of the Information-processing Perspective of Language Learning Process | 第9-10页 |
| Ⅱ． Significance of the Study of Output | 第10-13页 |
| 2．1 Equal Importance of Input and Output in Language Learning Process | 第10-11页 |
| 2．2 Insufficiency of Input for a Mastery of a Second/Foreign Language | 第11-12页 |
| 2．3 Problems in Current China's Foreign Language Teaching | 第12-13页 |
| Ⅲ． Rationale for the Function of Output in Language Learning | 第13-18页 |
| 3．1 Vygotsky's Theory of the Zone of Proximal Development | 第13-14页 |
| 3．2 Piaget's Learning Theory | 第14-16页 |
| 3．3 The Theory of Noticing in Cognitive Psychology | 第16页 |
| 3．4 Two Pairs of Psychological and Linguistic Notions | 第16-18页 |
| Ⅳ． Functions of Output in Language Learning | 第18-30页 |
| 4．1 Swain's Comprehensible Output Hypothesis | 第18-23页 |
| 4．2 Gass'Study of Output | 第23-26页 |
| 4．3 Skehan's Study of Output | 第26-27页 |
| 4．4 Two Tentative Hypotheses of Functions of Output | 第27-30页 |
| Ⅴ． Follow-up Studies of Output by the Present Writer | 第30-45页 |
| 5．1 A Study of Relationship Between Output Scaffolding and Foreign Language Learning | 第30-37页 |
| 5．2 Categories of Modification Moves Used by Native Chinese Learners of English in Output | 第37-45页 |
| Ⅵ． Setting Up Optimal Conditions for Output in Foreign Language Learning | 第45-56页 |
| 6．1 An Introduction of Task-based Approach | 第45-50页 |
| 6．2 An Integrated Framework of Foreign Language Learning | 第50-56页 |
| Ⅶ． Conclusion | 第56-58页 |
| Bibliography | 第58-60页 |
