| Code and code switching enter the sociolinguistic research for many decades, which at first concerns the language use or performance of a bilingual. In fact, code switching(hereafter CS) comes to be a common phenomenon in today's world, not only for those from distinct language backgrounds, but also for those under the same mainstream culture with different sub-cultures. One another important aspect includes that the CS in interaction is not at random but highly-organized, which also bears deep meaning, at the same time, constructs extra-linguistic significances in communication, so the applications of CS must be feasible and acceptable. This paper provides an overview of the theoretical&analytical questions, which are existing commonly in the study of the sociolinguistic dimension of code switching. In order to sort out the research about CS under sociolinguistic framework, it first looks at the earlier research on the CS, then reviews the modern sociolinguistic research on CS over the past three decades, focuses on the progressive and distinguished ideas about CS, and three key figures with their contributions in this field are introduced, in that they are the typical representatives in this field, which present the development route of research for CS, their points of views move up in spiral way. The meanings and functions of CS are mentioned in the sequent part, which are based on the previous researches. Its purpose is to serve as the foundation for the applications of CS in communication, the social and discourse meaning of CS from macro & micro perspective sometimes are overlapping. Trying to explore the extra-meaning of language choice is the main target of this part. Finally, the practical applications of CS in two fields—CS in intercultural communication and foreign language teaching are discussed. The possible application of CS roots out of many modern pragmatic theories such as adaptation theory, face theory etc., including its potential meanings. As an important pragmatic phenomenon and effective communicative strategy, CS in communication, especially in intercultural communication is widely used, our set-off is the emphasis of the feasibility in communication and try to solve the practical problem.In short, the intended contribution concentrates on the analysis and critics about the past works and excavates the possible implications of CS in practice, attaching importance on the applications of CS. The descriptive and analytic methods are used through the whole paper. |