位于句末的助词“在”有四种语法意义:A、对事态出现某种变化加以确认;B、表静态持续;C、表动作进行;D、表确信或申明语气。本文认为A类和B类“在”由位于句末的“在这里/那里”语法化而来,C类“在”则是B类“在”类化作用下的产物,D类“在”由位于句末的存在义动词“在”语法化而来。 There are four kinds of grammatical meanings at the end of a sentence: “A” has four kinds of grammatical meanings in “A”: A, confirming some change in a situation; B, a static state of the table; C, a table movement; This paper argues that Class A and B are grammaticalized from “here / where ” at the end of the sentence, while Class C “is ” under class B “under ” The D class “in ” is grammaticalized by the existential verb “at” at the end of the sentence.