摘 要
本文首先结合模糊语言的国内外研究实际探讨了它的起源和发展，指出它在语言中不可缺少的地位；然后阐述了商务英语的定义及其特点，并说明了模糊语言在商务英语信函中所起到的积极作用，如使商务英语信函中的商务语言表达的更加灵活，从而加强了礼貌性。适当的运用模糊语言，不仅会更准确的传达商务讯息，而且会拓宽人类想象的空间，让听话人更容易接受所说话语，从而增加其获准的机会；最后对中外商务英语信函中模糊用语的使用情况进行分析比较，并对今后如何更加恰当的使用模糊语言提出建议。
关键词：模糊用语；商务英语信函；礼貌原则
ABSTRACT
This paper first explores the origin and development of vague language combined with the research at home and abroad and points out its indispensible place. It then elaborates the definition and characteristics of Business English and shows the positive role of using vague language in business correspondence. That is, making business expression more flexible, thereby enhancing the courtesy. To be more specific，it not only makes the delivery of business message more accurate but also broadens human’s imagination. As a result, the listener is going to accept the information easily and the permissive chance will be increased. At last, the analysis and comparison of using vague language in business correspondence at home and abroad will be given and the feasible advice will be present.
Key words：Vague Language; Business Correspondence; Politeness Principle
Contents
1．Introduction 1
1.1 Necessity and significance of the study 1
1.2 Outline of the thesis 1
2. Vague language at home and abroad 3
2.1 Origin and definition of vague language 3
2.2 Clarification of some terms 6
2.3 Summary 8
3. Definition and characteristics of Business English 9
3.1 Principles of Business English 9
3.2 Necessity of using vague language in business correspondence 11
4. The Effect of vague language in business correspondence 13
4.1 Improving politeness 13
4.2 Enhancing the expression 15
5. Comparison and analysis of using vague language in business correspondence at home and abroad 18
6．Conclusion 22
Acknowledgements 23
References 24
