According to Chomsky, a language user’s underlying knowledge about the system of rules of his language is his linguistic ______. And ____ refers to the actual use of language in concrete situations. The task of a linguist is to determine from the data of ______ the underlying system of rules that has been mastered by the language user. Dell Hymes approaches language from a socio-cultural viewpoint and extends Chomsky’s idea of competence into _______ which has become very popular in EFL teaching in China.