| Acknowledgements | 第1-6页 |
| Abstract (Chinese) | 第6-7页 |
| Abstract (English) | 第7-9页 |
| Table of Contents | 第9-12页 |
| Chapter 1 The Theoretical Background | 第12-19页 |
| ·Principles and Parameters | 第12-13页 |
| ·The Model of Grammar | 第13-15页 |
| ·Feature Checking | 第15-17页 |
| ·Case | 第17-18页 |
| ·The Copy Theory of Movement | 第18-19页 |
| Chapter 2 The Assumptions on Null Subject Parameter | 第19-26页 |
| ·Against the Argument Status of Verbal Agreement | 第19-21页 |
| ·Against Identification via Verbal Agreement | 第21-23页 |
| ·The Morphological Uniformity | 第23页 |
| ·EPP is Speculative | 第23-26页 |
| Chapter 3 A New Approach to Null Subject Phenomenon | 第26-54页 |
| ·Obligatory Occurrence of a Subject ---a Universal Principle | 第27-33页 |
| ·The Occurrence of Subject as Predicate Licensing Condition | 第28-32页 |
| ·LF Subject | 第32-33页 |
| ·The Parametric Variation in Subject Combining | 第33-46页 |
| ·The Parameter of Feature Matrices of T | 第33-34页 |
| ·The Non-Uniform T-Projection | 第34-38页 |
| ·Subject Combining with the Support of Feature Checking | 第38-39页 |
| ·Subject combining in Non-inflectional Languages | 第39-46页 |
| ·The Lexical T in Chinese-Type Languages | 第40-42页 |
| ·A Subject in Adjoined Position | 第42-44页 |
| ·An Empirical Evidence for the Adjoined Subject | 第44-46页 |
| ·Summary | 第46页 |
| ·An Issue Related to LF Subject | 第46-49页 |
| ·The Obligatorily Spelt-Out Hybrid LF/PF Subject | 第49-52页 |
| ·The Visibility of Uninterpretable Feature | 第49-50页 |
| ·Overt Subjects Derived from PF Compensation | 第50-52页 |
| ·The LF/PF Hybrid Subject | 第52页 |
| ·The LF Subject in Italian | 第52页 |
| ·Conclusion for This Chapter | 第52-54页 |
| Chapter 4 The Testing of the Hypothesis | 第54-61页 |
| ·The Null Subject in Italian | 第54-58页 |
| ·The Overt Subject in English | 第58页 |
| ·The Null Subject in Chinese | 第58-61页 |
| Chapter 5 Some Related Issues | 第61-66页 |
| ·Deriving the Variation in Clause Projection | 第61-62页 |
| ·Related Issues Derived from Clause Projection | 第62-66页 |
| ·Topic Construction | 第62-64页 |
| ·The Non-nominal Subject | 第64-66页 |
| Chapter 6 Conclusion | 第66-68页 |
| References | 第68-70页 |
