1、在there + be的句型中，句子的主语是先行词，而且又是物。
例如：There are two novels that I want to read.我要读的有两本小说。
2、以Here is (are)开头的句子时。
例如：Here are two books that I will buy.这是我要买的两本书。
3、当先行词被the last，the very和the only修饰时。
例如：This is the very pen that I am looking for.这正是我找的钢笔。
4、在强调句子中，并且以who，which，what开头时。
例如：What was it that you did last week?你上周究竟做什么了？
5、当先行词被all，every，no，some，few，little，much，both等修饰时。
例如：This is all that I want to say at the meeting.这就是我在会上要说的。
6、当先行词有序数词时。
例如：You are the first person that I want to ask for.你是我要见的第一个人。
7、当先行词既指人又指物时。
例如：Let's talk about the persons and the things that we can remember.让我们谈论能够想起的人和事。
扩展资料
that的用法
1、that作指示代词
That is my book.那是我的书。
2、that作指示形容词
We haven't found any solution to deal with that problem yet.我们仍未找到解决问题的办法。
This is the sort of thing that Jeremy loves.这是杰里米喜欢的东西。
4、that作副词
that和this都可以作副词，用于修饰形容词或修饰另一个副词，表示“这么，那么，如此，这般”的意思。
It's about that long. 它大约有那么长。