如下：
1. 当先行词既指人又指物时。
They are talking about the persons and the things that they can remember.
他们正谈论能够想起的人和事。
2. 当先行词被the last , the very 和the only修饰时。
This is the very novel that I am looking for.
这正是我找的那本小说。
The only book I want to read is missing.
我唯一想看的书不见了。
3. 当先行词有序数词、最高级修饰时。
You are the first person that I want to see.
你是我要见的第一个人。
This is the best book that I have ever read.
这是我所看过的最好的一本书。
4. 当先行词被all, every, no , some, few , little, much, both等修饰或本身是先行词时。
This is all that I want to say.
这就是我要说的。
Have you any books that were written by LuXun?
你有鲁迅写的书吗？
5. 当先行词为anything、everything、nothing时，关系代词用that,不用which；
Everything we have seen in China is moving.
我们在中国看见的东西件件感人。
I have nothing that is worth reading.
我没有什么值得一读的东西。
6. 在 which 或who 的特殊疑问句中，为避免重复时。
Who is the boy that is standing there?
站在那的男孩是谁？
Which is your book that you bought yesterday?
哪本书是你昨天买的那本书？
7. 在there + be 的句型中，句子的主语是先行词，而且又是物。
There are two novels that I want to read.
我要读的有两本小说。
There is no homework that can be done now.
没有什么作业现在能做的了。
8. 以Here is (are)开头的句子时。
Here are two books that I want to read.
这是我要读的两本书。