| CONTENTS | 第2-3页 |
| Acknowledgements | 第3-4页 |
| Abstract （English） | 第4页 |
| Abstract （Chinese） | 第5-6页 |
| Chapter One Introduction | 第6-7页 |
| Chapter Two The Study of Vague Language and its Practical Implications | 第7-18页 |
| 1． The Study of Vague Language | 第7-10页 |
| 2． The Nature of Vague Language | 第10-13页 |
| 3． Pragmatic Vagueness and Relevance Principle | 第13-15页 |
| 4． Practical Implications | 第15-18页 |
| 4．1 Combination of the Implicit and Explicit Learning Style | 第15-16页 |
| 4．2 Improving Second Language Learners' Communicative Competence | 第16-18页 |
| Chapter Three The Influences of Vague Language on Second Language Learning | 第18-25页 |
| 1． Accuracy-Oriented Learning Style | 第18-20页 |
| 1．1 Intolerance of Ambiguity | 第18-19页 |
| 1．2 Utilizing Inappropriate Form and Level of Inexplicitness | 第19-20页 |
| 2． Pragmatic Failure of Second Language Learners in Cross-Cultural Communication | 第20-23页 |
| 2．1 Lacking Social-cultural Knowledge of the Target Language | 第21-22页 |
| 2．2 Lacking Knowledge of Flexible Selection in the Target Language | 第22-23页 |
| 3． Native-Like Fluency without Native-Like Selection | 第23-25页 |
| 3．1 Context-Independent Learning Style | 第23页 |
| 3．2 Lacking Knowledge of How, When and Why to Use Vague Language | 第23-25页 |
| Chapter Four The Applications of Vagueness Principles in Second Language Learning | 第25-34页 |
| 1． Fostering Awareness of Utilizing Vague Language | 第25-29页 |
| 1．1 Introducing Social-Cultural Knowledge of the Target Language | 第25-27页 |
| 1．2 Tolerance of Ambiguity | 第27-29页 |
| 2． Developing Some Cognitive Learning Styles of Inference and Guessing | 第29-30页 |
| 3． The Pragmatic Principles of Flexible Selection | 第30-34页 |
| 3．1 Flexible Selection of Vague Language | 第30-31页 |
| 3．2 Appropriate Selection of Structures | 第31-33页 |
| 3．3 Active Selection in Certain Context | 第33-34页 |
| Chapter Five Conclusion | 第34-35页 |
| Bibliography | 第35-36页 |
