語氣副詞“不一定”的主觀性研究

This article mainly attempts to analyze and study Chinese modal adverb “Buyiding”(不一定)from a cognitive and subjective perspective, which have become textual connections with a high frequency of utilization through the process of grammaticalization and attracted the extensive attention of the academic circles due to the semantic complexity between the previous and the following clauses. We expounds modal adverb “Buyiding”(不一定) emerging in the process of meaning expression and understanding in communication, and results from the variable, dynamic and adaptable properties of communication. Pragmatically increase discourse of the uncertainty, euphemism and courtesy in semantic function,in the development on semantic function it manifest the increase of subjectivity.