All of these definitions emphasize the difficulty of inferring the meaning of the idiom as a whole from the meaning of its constituent parts。 In accordance with many researchers of idiom processing, we could make such a definition: a conventionalized expression whose meaning cannot always be readily derived from the canonical meaning of tis constituent elements。 As cautioned by Cronk & Schweigert (1992), however, referring to an idiom as an accepted phrase or expression having a meaning different from the literal is not to say that the phrase cannot have a literal meaning, but rather than an idiom has an alternate, figurative meaning, which cannot be determined from the combination of the meanings of the inpidual words。 

    All in all, idioms play a very important role in our daily communication。 They are fixed units which must be included in complete language description。 In order to use idioms in a correct way to express our ideas, it’s necessary for us to do a further research of idioms from the perspectives of pragmatics and Speech act theory, which is the key point of this study。

1。2 The Aim of the Study

    After consulting studies carried out both at home and abroad on idioms, it can be concluded that previous studies mainly focus on the syntactic and semantic features of idioms, idiom translations and their classroom teaching。 But little has studied idioms in accordance with Speech act theory and explored how idioms can be used to perform various kinds of speech acts。 

    Hence, this dissertation aims to study the idioms from a new aspect: the Speech act theory and tries to indicate the pragmatic functions of them。 Through the study, the author hopes this work can help people better understand how idioms can be employed to perform different speech acts and how they function to effect successful communication。

1。3 Significance of the Present Research

Despite the existing idioms researches, this pragmatic study of idioms will be of significance both theoretically and practically。

On the one hand, this paper serves as a further application of pragmatics, which is a relatively young discipline, to academic research。 The current pragmatic researches of idioms, though large in amount, are far from sufficient。 Most of them discuss idioms from the perspective of translation, rhetoric, classroom teaching instead of doing a comprehensive pragmatic study of idioms。 In addition, the current idioms study, for the most part, remains theoretical, with few case studies。 

Such being the case, this paper tries to address idioms in pragmatic, with Speech act theory as its most powerful branch。 Besides, it will draw on examples from literary works as well as natural and spontaneous English conversations。 Altogether, this paper aims to provide a relatively all-around exploration of idioms production and appreciation, and to facilitate future researches。 

On the other hand, this paper is meaningful in terms of its practical application。 As has mentioned above, idioms assumes an important role in social life。 If used wisely, it can improve one’s interpersonal relationships by establishing rapport with others; if not, it may bring about disastrous consequences to one’s social life as a result of the offensive meaning it intended。 By probing into the production and functions of idioms, this paper reminds people of the significance of idioms in their life, which can help them to be more agreeable and to create a pleasant atmosphere where they can work more efficiently and effectively。 

Thus, in view of its academic value and practical application, this paper of idioms serves as a worthwhile and necessary study。

1。4 Organization of this Study

The dissertation is organized as follows。