自20世纪70年代早期以来,对模糊限制语的研究几乎涉及到语言学的各个方面。本文采用定量定性相结合的方法分析商务英语信函中模糊语的使用,并阐释其在不同信函中存在分布差异的成因及其在商务英语信函中的语用功能。研究发现,词汇型模糊语在商务英语信函中广泛存在,并且在不同信函中使用频率有所差异。同时,模糊语在商务英语信函中具有使语言表达更礼貌、更具说服力,更灵活等功能。本研究对深化认识模糊语的本质,语言实现方式及其语用功能有一定意义。同时有助于提高商务人士运用模糊语的意识,以促进商务交流的顺利进行。最后,本研究对商务英语教学具有一定启示。教师可在课堂教学中教授学生如恰当使用模糊语来实现其交际目的。 Since the early 1970s, the study of hedges has involved almost all aspects of linguistics. This paper analyzes the use of fuzzy words in business English letters by means of quantitative and qualitative methods and explains the causes of their differences in different letters and their pragmatic functions in business English letters. The study found that vocabulary-based vagueness exists widely in business English letters and has different frequency of use in different letters. At the same time, vague language has the functions of making the language more polite, more persuasive and more flexible in business English letters. This study is of some significance to deepen the understanding of the nature of vague language, language realization and its pragmatic functions. At the same time help to improve business people to use fuzzy language awareness, to promote the smooth progress of business exchanges. Finally, this study has some enlightenment on Business English teaching. Teachers can teach students in classroom teaching appropriate use of vague language to achieve their communicative purposes.