他们谈论了他们在这所学校能记起的事和人。

　　⑤句子中出现过which或who之类的词，为了避免重复，要用that。

　　Which of the books that had pictures was worth reading?

　　哪本有图画的书值得读呢？

　　(3) 在限制性定语从句中只用which不用that的情况：关系代词前有介词时，一般用which，而不用that。

　　This is the room in which he lives.

　　这是他居住的房间。

　　2．who和whom的用法

　　who和whom指人，who在从句中可作主语和宾语，whom在从句中作宾语。

　　There is a girl who wants to see you.

　　有个女孩儿想见你。

　　He is the man (who/whom) I saw yesterday.

　　他就是我昨天见到的那个人。

　　3．whose 既可指人也可指物，在从句中修饰名词作定语。它可以转化为"the＋名词＋of which/whom" 和"of which/whom＋the＋名词"的形式。

　　This is the scientist whose name is known all over the country.

　　＝ This is the scientist the name of whom is known all over the country.

　　这就是那位全国知名的科学家。

　　Please pass me the book whose cover is green.

　　＝Please pass me the book the cover of which is green.

　　请递给我那本绿色封面的书。

　　4．as引导限制性定语从句的用法

　　as引导限制性定语从句仅限于先行词前面有such, the same等修饰时，as既可指人又可指物，在定语从句中充当主语、宾语等。

　　She is such a nice girl as we all like.

　　她是一个我们大家都喜欢的好女孩。

　　[比较]She is such a nice girl that we all like her.(结果状语从句)

　　她是一个如此好的女孩以至于我们都很喜欢她。

　　I bought the same dictionary as you borrowed.

我买了一本和你借的词典一样的词典。(同一类的两本词典)