| 内容提要 | 第1-6页 |
| Synopsis | 第6-10页 |
| Chapter 1 Introduction | 第10-14页 |
| Chapter 2 Literature Review | 第14-43页 |
| ·Researches on the Terminology of Vagueness | 第14-27页 |
| ·Definition of Vagueness | 第14-18页 |
| ·Differences among Vagueness,Fuzziness,Ambiguity and Generality | 第18-21页 |
| ·Previous Researches on Vagueness | 第21-27页 |
| ·Pragmatic Vagueness | 第27-31页 |
| ·Definition of Pragmatic Vagueness | 第27-29页 |
| ·Application of Pragmatic Vagueness | 第29-31页 |
| ·Three Main Theories to Analyze Vagueness in the Present Research | 第31-37页 |
| ·Basic Concepts of Context | 第31-34页 |
| ·Theory of Adaptatibility | 第34-35页 |
| ·Relevance Theory | 第35-37页 |
| ·Overview of English Business Letters | 第37-43页 |
| ·Classification of English Business Letters | 第38-39页 |
| ·Principles of English Business Letters | 第39-42页 |
| ·The Previous Studies on Vague Language in English Business Letters | 第42-43页 |
| Chapter 3 The Analysis of Pragmatic Vagueness in English Business Letters | 第43-78页 |
| ·Data Collection and Analysis | 第43-44页 |
| ·Employment of Pragmatic Vagueness in English Business Letters | 第44-63页 |
| ·Employment of Pragmatic Vagueness in English Business Letters of Good and Neutral News | 第44-54页 |
| ·Employment of Pragmatic Vagueness in Bad-news Letters | 第54-59页 |
| ·Employment of Pragmatic Vagueness in Persuasive Letters | 第59-61页 |
| ·Data Analysis and Summary | 第61-63页 |
| ·Passive Pragmatic Vagueness vs.Active Pragmatic Vagueness | 第63-78页 |
| ·Analysis of Passive Pragmatic Vagueness | 第63-67页 |
| ·Cognitive Differences on Meanings | 第64-66页 |
| ·The Limitation of Language Expressions | 第66-67页 |
| ·Analysis of Active Pragmatic Vagueness | 第67-78页 |
| ·Context:The Carrier of Active Pragmatic Vagueness | 第67-70页 |
| ·Adaptation:The Addresser's Strategy | 第70-75页 |
| ·Optimal Relevance:The Addressee's Deduction | 第75-78页 |
| Chapter 4 Functions of Pragmatic Vagueness in English Business Letters | 第78-88页 |
| ·Making English Business Letters More Polite | 第78-81页 |
| ·Improving the Flexibility | 第81-83页 |
| ·Enhancing the Appropriateness | 第83-85页 |
| ·Establishing Self-Protection | 第85-88页 |
| Chapter 5 Conclusion | 第88-91页 |
| Bibliography | 第91-96页 |
| Appendix:Sample Business Letters | 第96-121页 |
| Abstract(Chinese) | 第121-127页 |
| Abstract(English) | 第127-137页 |
| Acknowledgements | 第137页 |
