【正文】 icing pleteness and concreteness. Generally speaking, we will gain in conciseness by writing short sentences rather than long ones.6) CourtesyCourtesy means to show the honest friendship, thoughtful appreciation, sincere politeness, considerate understanding and heartfelt respect tactfully in our letters. A letter expressed in the way of refined and courteous can make ourselves set up an honest and enthusiastic image, which may make the readers glad to cooperate with us.7) ConsiderationA business letter can function well only if it can deeply impress on its recipient. To gain such a favorable impression and influence, we should put ourselves in the position of the recipient, taking into consideration his demand, hope, interests, etc. Thoughtful consideration enables us to better understand our recipient, thus our requirement will be more practical and understandable. The Cooperative Principle It is said that American philosopher Paul Grice began to formulate his ideas of the theory of conversational implicature in the 1950’s, but it was first became known to the public in 1967 when he delivered lectures at Harvard. He concluded that natural language had its own logic. His idea is that in making conversation, the participants must first of all be willing to cooperate. This general principle is called the Cooperative Principle. Definition of Cooperative Principle and its MaximsPeople are always observing a certain rules in verbal munication。 secondly, to make or to accept an offer。 thirdly, to deal with matters concerning negotiation of business” (外經(jīng)貿(mào)英語(yǔ)函電, 1989: 1).Good munication is so essential in business activities that it requires principles to guide munication. Business letters, as one of a firm39。 otherwise, munication will not proceed any more. In view of this, people do not usually say things directly but tend to imply them which called implicature.Grice’s opinion is that there is some regularity in conversation.“Our talk exchanges do not normally consist of a succession of disconnected remarks, and would not be rational if they did. They are characteristically, to some degree at least, cooperative efforts。 my lips are sealed when he has no obligation to let information out.3) He may be faced by a clash. That is to say, he may have to violate one maxim in order to fulfill another. For example, he may be unable to fulfill the first maxim of Quantity without violating the second maxim of Quality.4) He may deliberately violate one of the maxims or fail to fulfill it. When a maxim is flouted, a speaker does not observe the maxim. In this case, the speaker not only knows he is not observing it, but realizes everyone else in the conversation knows it too.It is clear that no implicature would arise in the first and second ways of violation because there is no such basis as CP. However, the third and the fourth ways of violation do lead to implicature in munication. And this aspect arouses the interest of many scholars which produced a great number of studies. But implicature will not be studied in this thesis, for in business letters the theme will be clearly showed but not to be implied.3. Application and Analysis of the Cooperative Principle in Business LettersFrom the above mentioned content, we have a basic understanding about business letter and cooperative principle. In order to give help to further understanding, this thesis is going to analyze the application of cooperative principle in business letters.Every business letter, as a matter of fact, is a munication event. Furthermore, the criterion of distinguishing the effective business letters from the bad ones lies in whether the recipient’s understanding of the message is consistent with the sender’s purpose. It means that writing business letters should observe the cooperative principle。 in contrast to sentence 3A, the 3B sentence is much shorter and clearer without losing any information. The Maxim of Quality in Business LettersThis maxim means not to say what you believe to be false and for which you lack adequate evidence. 4A) We ordered welldried goods of fine quality, but you have sent us prunes totally unmerchantable and unfit for consumption.4B) We ordered welldried goods of fine quality, but you have sent us prunes totally in a halfrotten state.This sentence 4A can be easily found in the letters of plains and claims, which specially needs careful wordchoosing by using specific words instead of vague ones. In this case, the writer uses vague phrase to plain failing to state the degree of goods’ bad quality. Sentence 4B makes it more specific by using “in a halfrotten state” to replace the vague one.Furthermore, in order to ply with the maxim of quality, we should also make sure that the diction and data should be correct and true.5A) Our washingmachine has its unusual design. 5B) Our washingmachine has its unique design.In 5A sentence, “unusual” means different from what is usual or normal, while “unique” of 5B sentence is being the only one of its kind. From their meanings, we consider “unique” will be more suitable for the product introduction, for it can show distinction of washingmachine. The Maxim of Relation in Business LettersThe maxim of relation suggests relating every details of the letter. In written munication, the reply should be relevant to receiving letter for the further munication. The relevant maxim is the primary and most important condition to plete the intermunication.6) We would like you to send us details of your various ranges, including sizes, colors, prices, and also samples of the different qualities of material used.Reply: We are enclosing our illustrated catalogue and price list giving the details you asked for. Also by separate post we send you some samples.In this example, the reply has offered the relevant information about the products by sending a catalogue. All of these have achieved the requirement of th