Constructivism provides us with a new approach to study individual cases such as human rights,trade frictions,and arms embargo,in order to analyze the process of building-up shared knowledge and constructing identities and interests through social learning of bilateral interactions.

This paper holds that shared knowledge plays an important role in communication because shared knowledge will affect the choice of information.

The shared knowledge reached at as the result of utterance choice sets confinement on and provides the drive for turning-taking,while allowing for the conversational implicature as "missing links" and "silence" in response turns.

Analysis common knowledge and knowledge sharing of enterprise;

Because each individual society has its own common knowledge and each language has its own dimensions and customs,translaters must tend to seek the most proper information for translation readers to appreciate.

Starting from the perspective of foreign language acquisition,this paper holds that there exists a close relationship of common knowledge between the learning and different nations,and also believes that the process of foreign language learning should be a process of reflecting,conflicting,uniting and interpreting between the two cultures.

This paper discusses the presupposition theory in pragmatics and illustrates several aspects of the theory,including semantic presupposition,pragmatic presupposition,focus,mutual knowledge,the relations between presupposition and context,and presupposition triggers.

Implicature depends on the contxual information of utterances and the mutual knowledge of the communicators,that is,the inferences of implicature cannot depend.

The knowledge resources have been eroded,caring for the intellectual commons even more urgent.