“体”范畴是语言学的重要研究领域之一,在传统意义上,“体”范畴被认为是动词的一种语法范畴,它侧重表示动作或事件的进程。“了”是一个表示“体”范畴重要的词之一。本文将从认知语言学的角度寻找动态助词“了”的使用条件,主要参考石毓智的研究成果,但提出了本人的一些拙见,愿可以很好地诠释它诸多用法产生的缘由。 The “body” category is one of the important research fields of linguistics. Traditionally, the category of “body” is considered as a grammatical category of verbs, and it focuses on the process of expressing actions or events. “A ” is one of the most important words in the category of “body ”. This article will look for the conditions for using the dynamic auxiliary word “a ” from the perspective of cognitive linguistics, mainly referring to the research results of Shi Yuzhi, but put forward some of my own humble opinions and may well explain the reasons for its many usages.