上古汉语的指示词“是”主要用于外指和回指,这两种功能基本上都与距离意义无关,因此很难说它是近指词;同样,在上古汉语中,也没有充分证据能够证明“是”在语义上与“此”“彼”构成明显的三分对立关系,可见这三个指示词并不处在同一个语义层级系统中,因此指示词“是”也并非中指词。文章认为,上古汉语的指示词“是”在语义功能上主要起加强所指称对象的有定性的作用,它不像“此”“彼”那样具有强烈的指别意义,因此,把它看作一个纯粹中性的指示词或者定指词较为妥当。 The ancient Chinese demonstrator “is ” is mainly used for both the outer and the anaphora, and these two functions are basically independent of the meaning of the distance, so it is hard to say that it is an index finger; similarly, there is not enough in ancient Chinese Evidence can prove that “yes ” has a clear antithesis to “this ” “he ” constitutes a clear three-point relationship, we can see that these three directives are not in the same semantic level system, so the directives “Yes ” is not the middle finger. The article argues that the indicator of ancient Chinese, “是”, plays a qualitative role in semantic function mainly to strengthen the alleged object. It does not have strong meaning as “” " Therefore, it is more appropriate to regard it as a purely neutral or fixed reference.