六用: （1）先行词为all, everything, anything, nothing, something（也可which）,few, little, much等或先行词被all, every, any, no, little, much修饰时。如： All that can be done has been done. 所有能做的事都已经做了。 Is there anything that I can do for you? 有什么需要我做的吗？ There is not much that can be done. 没有什么可做的了。 You can take any book that you like. 你可以拿你喜欢的任何一本书。 I have read all the novels that you gave me. 你给我的小说我都看完了。 （2）先行词为形容词最高级或先行词被形容词最高级修饰时。如： His article is the best that has ever been written on the subject. 他的文章是有关这一题目的最好的。 This is the best book that I have ever read. 这是我所读过的最好的书。 （3）先行词为序数词或先行词被序数词修饰时。如： This is the first time that I heard of it. 这是我第一次听说此事。 The last place that we visited was the Great Wall. 我们参观的最后一个地方是长城。 （4）先行词被the only, the very, the right等修饰时。如： This is the very watch that I lost the other day. 这就是我那天丢的那块表。 注：以上（2）（3）（4）若先行词指人时，也可用who, whom，但常用that。如： He was the first that / who was there. 他是第一个到达那里的人。 You are the only person that / who can help me. 你是唯一能帮我的人。 （5）先行词包括人和物两者时。如： They talked about things and persons that they remembered in the school.他们谈论了他们记得的在学校里的人和事。 期刊文章分类查询,尽在期刊图书馆 He talked happily of the men and the books that interested him. 他高兴地谈到了他感兴趣的人和书。 （6）当主句是以who或which开头的特殊疑问句时。如： Who is the person that is standing at the gate? 站在大门口的那个人是谁？ Which of us that knows something about physics does not know this? 我们凡是了解物理的有谁不知道这个呢？ 三不用: （1）先行词是用-one或-body构成的复合不定代词时，不能用that，而用who, whom。如： Is there anybody else who should be invited? 还该邀请谁？ （2）关系代词前有介词时，不能用that，而用which, whom。如： Here is the car about which I told you. 这就是我跟你说起的那辆车。 Who is the man with whom you just shook hands? 你刚才跟他握手的那个人是谁？ （3）在非限制性定语从句中，不能用that，而用who, whom, which。如： I have lost my pen, which I like very much. 我很喜欢我的钢笔，但它丢了。 I have two sisters, who are both students. 我有两个妹妹，她们都是学生。