【正文】 gue. Let’s consider, for example, the word ‘tall’. There is no precise, known height that defines the line between a person who is tall and a person who is not. Why do we use a language in which such words are so prevalent? Why don’t we simply adopt as a definition that ‘tall’ will mean above, say, 6foot2? We could even adopt a contextspecific definition, saying for example that ‘tall’ for a newborn means above 15 inches, while ‘tall’ for a professional basketball player means above 6foot10.If any word we use had to be given such a specific definition, there would be a great efficiency loss in munication. And it is obviously easier to municate when one is allowed to use vague language. Most speakers of English are not particularly aware of the frequent use of vague language (unless it is pointed out to them) and this fact is in itself of interest. It shows that vagueness in munication is part of our takenforgranted world, and that normally we do not notice it unless it appears inappropriate – for example, when someone seems to be deliberately withholding information. This makes vagueness like many other linguistic phenomena, which pass unnoticed until an investigating linguist argues that they are worthy of description. An example is metaphor, which appeared to be an esoteric issue until the publication of Metaphors We Live By (Lakoff and Johnson 1980). In that book, the authors point out that speakers often do not realize that the language they are using is metaphorical. Likewise, experts found out that people often do not realize that the language they are using is vague.There are many different standards regarding the use of language. Clarity and precision maybe are the most important. Hence, people generally believe that vagueness should be avoided. I would like to say that this is rather too simple a view, and likely to be positively misleading as an instruction to those who are learning how to write. Many good writers demonstrate their petence through their use of a certain degree of vagueness that is right for the purpose of their writing. This is the key to understanding that vagueness in language is neither all ‘bad’ nor all ‘good’. What matters is that vague language must be used appropriately.In legal system, the use of language is crucial because that lawmakers use language to make laws, and courts use language to state their grounds for conferral. Legal language is concerned with the imposition of obligations and conferring of rights. In terms of mode, legal language is mainly recorded in a written form being essentially a visual language meant to be scrutinized. Though, for instance, court trial is conducted in spoken form, the language used at court shares much with the characteristics of written legal documents.In this thesis, I confine myself to the language used in written legal documents. In order to ensure that a document says exactly what it is meant to say, and leaves no chance for misinterpretation, posers of the document will take the greatest pains to make it municate just one set of meanings and avoid any possible ambiguity. But we cannot deny that, owing to some reasons, we need to use vague language in legal documents so as to achieve what we mean to have. It may seem inconsistent that vague language can also serve the purpose of preciseness in legal documents. As a matter of fact, appropriate use of vague language is important to legal documentation and thus deserves more analysis than it has so far received, especially when China now is a member of World Trade Organization (WTO), which provides China with a lot of opportunities of getting involved in international lawmaking.Awareness of vague expressions appearing in English legal documents will prepare us for disputes arising from international trade, and will grant us the chances of taking advantage of international laws so as to safeguard our national interests. However, the investigation of the vagueness of legal language is quite limited, though we have many scholars who study vague linguistics or legal linguistics. In this thesis, I try to carry out a tentative research concerning vagueness in law English. Chapter Two Vague Language What is vague language?Interest in vagueness has arisen in a number of disciplines: linguistics, psychology, philosophy, etc. In this chapter I would like to introduce the general notion of vague language by outlining some existing approaches in the three disciplines.The discipline of linguistics Ullmann in an essay entitled ‘Words with blurred edges’ traced from Plato to Byron a recurrent feeling of the inadequacy of language to express thought, particularly because language is lack of precision. He noted also the converse feeling among poets and creative writers that such vagueness is in fact an advantage. This idea has also been reflected by Wittgenstein who suggests that words are like blurred photographs and adds, ‘Is it even always an advantage to replace an indistinct picture by a sharp one? Isn’t the indistinct one often exactly what we need?’Ullman goes on to point out another important aspect of vagueness. He notes that: If one looks more closely at this vagueness, one soon discovers that the term is itself rather vague, and ambiguous: the condition it refers to is not a uniform feature but has many aspects and may result from a variety of causes. Some of these are inherent in the very nature of language, whereas others e into play only in special circumstances.① ① Joanna Channell： Vague LanguageHe attributes vagueness to the generic character of the words we use. He says that what words refer to are ‘not single items but classes of things or events bound together by some mon element’. For example, there is a class of things referred to in English by the term bird, but if we look at it in more detail, we see that some birds are very typically ‘bird’(robin), while other birds (ostrich, penguin) do