指示代词分单数（this / that）和复数（these / those）两种形式，既可作限定词又可做代词。表示“这个”、“那个”、“这些”、“那些”等指示概念的代词叫做指示代词。指示代词有this，that，these，those等。

单数/复数:

限定词：This girl is Mary. Those men are my teachers.

代词： This is Mary. Those are my teachers.

指示代词的句法功能；

a. 作主语

This is the way to do it. 这事儿就该这样做。

b. 作宾语

I like this better than that. 我喜欢这个甚至那个。

c. 作主语补语

My point is this. 我的观点就是如此。

d. 作介词宾语

I don't say no to that. 我并未拒绝那个。

There is no fear of that. 那并不可怕。