定语从句一概念1.定语从句：就是在复合句里充当定语的从句，它通常紧靠在所修饰的名词或代词后面。2.先行词：就是被定语从句修饰的名词或代词。3.关系词：引导定语从句的词叫关系词。关系代词who, whom, whose, which, that；在从句中可作主语、宾语、定语、表语等关系副词 when, where, why，在从句中作状语。如：This is the book that my father bought me yesterday. 这就是我父亲昨天帮我买的那本书。The time when he arrives is not known. 他到达的时间还不知道。二关系代词 1.先行词是人，在从句中作主语用who，作宾语用whom或who，作定语用whose；Eg: This is the man who helped me.The boy whom/who you are looking for is in the room.Do you know the man whose name is Yao Ming?2.先行词是物，在定语从句中作主语或宾语都用which，作定语用of which或whose均可。在限制性定语从句中which, who, whom都可用that代替。关系代词作宾语时常被省略。This is the factory (which/that) we visited last year.这就是我们去年参观的那家工厂。He has a book whose cover (=the cover of which) is very beautiful. 他有一本封面非常漂亮的书。习惯上要用that引导的定语从句(1)当先行词是指物的all, little, few, much, any, anything, everything, nothing, none, the one时，或先行词被all, little, few, much, any, every, no等修饰时。He will tell you everything that he heard about it.他将告诉你他所听到的关于这件事的一切。There is little work that is fit for you. 没什么工作适合你做。I have eaten all the food that is left. 我把剩下的所有食物都吃了。(2)先行词是序数词或最高级形容词时，或者先行词被序数词(包括last, next)、最高级形容词及the only, the very 等修饰时。This is the first film that I have seen since I came here.这是我到这里后所看的第一场电影。This is the very book that I am looking for. 这正是我一直在寻找的那本书。(3)先行词包括人和物时。They often talk about the people and the things that they are interested in. 他们常常谈论那些他们感兴趣的人和事。(4)当主句是以who或which开头的疑问句时，为了避免重复，多用that引导。如：Which is the house that caught fire last night? 昨晚失火的是那座房子？Who is the lady that is playing the piano? 在弹钢琴的那位小姐是谁？（5） 当关系代词在定语从句中用作表语时，通常用that：China is not the country (that) it was. 中国已不是过去的中国了。习惯上不用that引导的定语从句(1)在非限制性定语从句中，不以能用that引导。Yesterday I met Mary, who seemed very excided. 昨天我碰到了玛丽，她显得非常兴奋。(2)直接在介词后作宾语时，不能用that引导，要用whom, whose或which，且不能省略。The house in which we live is not large. 我们住院的房子不大。I know the young man with whom you live. 我认识和你住在一起的那个年青人。注：当介词放在从句的末尾时，可以用that替代which, who替代whom，也可以省略关系代词。如：The house (which/that) we live in is not large. 我们住院的房子不大。I know the man (whom/who/that) you live with. 我认识和你住在一起的那个人。(3)当先行词是指人的all, any, few, one(s), anyone, everyone,people 等时，多用 who。如：Anyone who is over sixteen is allowed in. 任何超过十六岁的人都允许进去。I met someone who said he knew you. 我碰到一个人，他说认识你。三关系副词关系副词有when, where, why，在定语从句中作状语，分别表示时间、地点和原因。其中why的先行词只能是reason。关系副词when和where有时可用“介词which”代替，why可用for which代替。如：Beijing is the place where (=in which) I was born.北京是我的出生地。Is this the reason why (=for which) he refused our offer?这就是他拒绝我们帮助他的理由吗？注意：先行词虽然是时间或地点，但若在定语从句中作主语或宾语时，要用关系代词。(1)The factory where his father worked has closed. 他父亲曾工作的那家工厂关闭了。(作状语)比较：The factory which/that was built in 1978 has closed. 1978年建的那家工厂关闭了。(作主语)(2) Ill never forget the days when we lived together. 我永远也忘不了我们一起生活的那些日子。(作状语)比较：Ill never forget the days (that) we spent in Australia. 我永远也忘不了我们在澳大利亚度过的那些日子。(作及物动词spent的宾语)(3) The reason (why) she was ill was that she had eaten bad meat. 她生病的原因是她吃了变质的肉。(作状语，用关系副词)比较：The reason (that) he gave for his absence was obviously fabricated.他所说的缺席理由显然是编造的。(作gave的宾语，用关系代词)四限制性定从和非限制性定从1.限制性定从是句中不可缺少的部分，主句和从句之间不用逗号2.非限制性定从是对主句的补充说明，一般用逗号把主句和从句分开。He has two sisters, who are both students.He has to go to school tomorrow, which he doesnt like.五as 的用法1.用作关系代词或关系副词引导限制性定从，构成the same as, suchasI want to have such a book as he has.2.as引导非限制性定从，先行词为整个句子，as可以放在主句之前。As is known to us, he is the best student in our class.注：关系代词在从句中作主语时，从句的谓语动词与先行词一致。1.The place _interested me most was the Childrens Palace. A. which B. where C. what D. in which 2.Do you know the man _? A. whom I spoke B. to who spoke C. I spoke to D. that I spoke 3.This is the hotel _last month. A. which they stayed B. at that they stayed C. where they stayed at D. where they stayed 4.Do you know the year _the Chinese Communist Party was founded? A. which B. that C. when D. on which 5.That is the day _Ill never forget. A. which B. on which C. in which D. when 6.The factory _well visit next week is not far from here. A. where B. to which C. which D. in which 7.Great changes have taken place since then in the factory _we are working. A. where B. that C. which D. there 8.This is one of the best films _. A. that have been shown this year B. that have shown C. that has been shown this year D. that you talked 9.Can you lend me the book _the other day? A. about which you talked B. which you talked C. about that you talked D. that you talked 10.The pen _he is writing is mine. A. with which B. in which C. on which D. by which 11.They arrived at a farmhouse, in front of _sat a small boy. A. whom B. who C. which D. that 12.The engineer _my father works is about 50 years old. A. to whom B. on whom C. with which D. with whom 13.It there anyone in your class _family is in the country? A. who B. whos C. which D. who