摘  要

商务信函一直以语言具体、简洁、准确和清晰为写作原则，并遵照传统的“7C”原则。这似乎给我们传达了一个信息：在商务信函写作中要避免使用模糊的语言。但在实际的应用中，不难发现，模糊语在商务信函中的应用甚广。本文的第一章将讲述该研究的背景，意义及目标。第二章对模糊语及商务信函的文献综述。第三章主要介绍了顺应论及礼貌原则的理论框架及本文所用到的研究方法。第四章结合实例来分析在顺应论视角下模糊语的积极作用。第五章指出了本文的主要研究成果，不足之处以及未来的研究方向。通过研究，有助于更好地理解模糊语，提高人们的商务写作水平，更好、更有效的表达发件人的意图，让商务沟通更有效地进行。

关键词：商务信函；模糊语言；顺应论；礼貌原则；积极作用

Abstract

Business correspondence plays a crucial role in international trade exchanges. It is a form of business English, whose language has been based on the principle of being specific, concise, precise and clear, guided by "Seven Cs" principle. So it seems to convey a message to us: when writing business letters, vague language should be avoided as much as possible lest a pragmatic vagueness appears. However, in practical applications, after analyzing a lot of business correspondence, we find that the vague language is still used widely in business letters. This paper consists of five parts. The first chapter is a brief introduction to this paper, which describes the research background, significance and objectives. The second chapter is a literature review on the vague language and business correspondence. The third chapter mainly deals with theoretical framework of adaptation theory and methodology used in this paper. The fourth chapter analyzes the positive role of vague language in the perspective of adaptation theory with practical examples. The fifth chapter points out the main research findings of this paper, limitations and suggestions for the further study. Through the research, it helps us to have a better understanding of vague language, and to use it more accurately, increasing the flexibility of the language, improving people's business writing level, effectively expressing the sender's intention and better understanding the vague language and making communication more effective.

Key words: business correspondence; vague language; adaptation theory; politeness principle; positive function