1)修饰人的定语从句

　　who 主语/宾语(口语中，可省略)

　　that 主语/宾语(可省略，前面不能有介词)

　　whom 宾语(前面没有介词时可省略)

　　whose 定语

　　Do you know the person to whom he is talking?

　　Do you know the person(whom/that) he is talking to?

　　He is the man (who/whom/that) you can rely on.

　　He is the man on whom you can rely.

　　Do you know the woman who(that) is watching TV?

　　You're the only one whose advice he might listen to.

　　The girls whose names were called stood up.

　　Here is the man (whom/that) you've been looking for.

　　He is a man on whom you can safely depend.

　　2)修饰物的定语从句

　　如果修饰的词是物，而它在定语从句中做主语，则可以用that和which.

　　如果修饰的词是物，而它在定语从句中做宾语，则可以用that(可省略，前面不能有介词)和which(前面没有介词时可省略)。

　　whose后接名词做定语。

　　She wasn't on the train which /that arrived just now.

　　The dog which/that was lost has been found.

　　This is the question about which we've had so much discussion.

　　This is the question(that/which) we've had so much discussion about.

　　The novel (that/which) he recommended is worth reading.(be worth doing;值得做某事)