【Abstract】By the late 1960s， mutual understanding between different language communities was greatly needed. The main goal of learning a foreign language become focus―more attention being paid to learning language for communicating. This article introduces theory of communicative competence from teachers’ aspect and makes a comparison between linguistic competence and communicative competence. At last， we explore some of its influences on second language teaching resulting in newly popularized communicative language teaching（CLT）.
　　【Key words】communicative competence； language teaching； CLT
　　Ⅰ. Introduction
　　What goals do learners want to achieve by learning a language especially a foreign language？ To master some important grammars or sentence structures， or to show their ability to learn something fast？ Only when teachers get this point can they better teach learners..
　　Language is a system of arbitrary vocal symbols used for human communication. It is important to remember the term “used for human communication”.No matter what specific aims learners have， the primary and final goal is to communicate with others better. ESL learners’ final goal is to communicate with foreigners in English efficiently. Therefore the communicative competence is of great importance.
　　Ⅱ. Theoretical Basis of Communicative Competence
　　American linguistic-anthropologist Hymes（1972） first proposed communicative competence. Hymes’s theory of communicative competence was a definition of what a speaker needs to know in order to be communicatively competent in a speech community.Hymes thought language learning is learners acquire both grammatical knowledge and linguistic competence and language teaching is teachers teach both linguistic competence and communicative competence.
　　Communicative competence was developed by Canale and Swain（1983）.They identify four distinctive components including grammatical competence， sociolinguistic competence，discourse competence and strategic competence.Riehards and Platt’s showed，the most outstanding one，showed four aspects of communicative competence.
　　1. Definition of linguistic competence and communicative competence
　　Chomsky defines competence as a language user’s underlying knowledge about the system or rules of that language.In Chomsky’s view， the native speakers’ competence can be characterized as a set of rules for producing an understanding of sentences in his language. To acquire the native speakers’ competence is to obtain the ability to recognize and produce grammatically correct sentences in a language. He argues that a native speaker possesses a kind of linguistic competence. 　　Dell Hymes points out that Chomsky’s competence is necessary but not sufficient for a learner to communicate with others successfully in a speech community. In addition to grammatical accuracy，a successful communication required appropriateness in the sense that speakers of a language know when they speaks what to whom.
　　2. Comparison between linguistic competence and communicative Competence
　　（1） Similarity. Both linguistic competence and communicative competence are abstract and idealized concepts and they contrast with performance which is the actual realization language behavior. Both of them can be called theories which will provide guidelines for language practice and can be internalized by each individual over time.
　　（2） Difference. Firstly， communicative competence is wider in scope than linguistic competence. Linguistic competence merely concerns the user’s internalized language rules and it ensures that the generated language phenomena are grammatical. While communicative competence， especially its sociolinguistic competence and strategic competence components involves other language possessing stages，such as understanding and expressing in which both the speaker and the listener are involved（Yang，2002）. In addition， it includes nonverbal communication as well as verbal communication. Secondly， their emphasis is quite different in verbal manner. Linguistic competence places emphasis on the form of the language and relates little to what the language is used for， while communicative competence takes the function of language as its priority and it does not ignore the importance of language form.
　　（3） Interrelationship.Communicative competence aims to make language users more flexible while linguistic competence aims to make language users more and more accurate.Despite differences， these two interrelate with each other. For accuracy， language users must accumulate knowledge about language as much as possible. Only on the basis of adequate accumulation of linguistic expressions can one realize the expectation of using language flexibly. In a word， accurate linguistic form will make for effective communication. Linguistic competence is not equal to communicative competence（Chen