关系词有关系代词和关系副词。关系代词有that, which, who, whom, whose, as等；
关系副词有where, when, why等。
(1) The boys who are playing football are from Class One.
(2) Yesterday I helped an old man who lost his way.
(1) Mr. Liu is the person (whom) you talked about on the bus.
(2) Mr. Ling is just the boy whom I want to see.
(3) The man who/whom you met just now is my friend.
(1) Football is a game which is liked by most boys.
(2) This is the pen (which) he bought yesterday.
(5) The number of the people that/who come to visit the city each year rises one million.
(6) Where is the man that/whom I saw this morning?
(1) He has a friend whose father is a doctor.
(2) I once lived in a house whose roof has fallen in.
(3) The classroom whose door is broken will soon be repaired.
(4) The classroom the door of which is broken will soon be repaired.
(5) Do you like the book whose cover is yellow?
(6) Do you like the book the color of which is yellow?
(1) The school (that/which) he once studied in is very famous.
(2) The school in which he once studied is very famous.
(3) Tomorrow I will bring here a magazine (that/which) you asked for.
(4) Tomorrow I will bring here a magazine for which you asked.
(5) We”ll go to hear the famous singer (whom/that/who) we have often talked about.
(6) We”ll go to hear the famous singer about whom we have often talked.
注意：1.含有介词的动词短语一般不拆开使用，如：look for, look after, take care of等
(1) This is the watch which/that I am looking for. (T)
(2) This is the watch for which I am looking. (F)
(1) The man with whom you talked is my friend. (T)
(2) The man with who/that you talked is my friend. (F)
(3) The plane in which we flew toCanadais very comfortable. (T)
(4) The plane in that we flew in toCanadais very comfortable. (F)
3.“介词+关系代词”前可有some, any, none, both, all, neither, most, each, few等代词或者数词
(1) He loved his parents deeply, both of whom are very kind to him.
(2) In the basket there are quite many apples, some of which have gone bad.
(3) There are forty students in our class in all, most of whom are from big cities.
(1) I still remember the day when I first came to the school.
(2) The time when we got together finally came.
(1) Shanghai is the city where I was born.
(2) The house where I lived ten years ago has been pulled down.
(1) Please tell me the reason why you missed the plane.
(2) I don”t know the reason why he looks unhappy today.
(1) The reason why/ for which he refused the invitation is not clear,
(2) From the year when/in which he was going to school he began to know what he wanted when he grew up.
(3) Great changes have taken place in the city in which/where I was born.
(1) The teacher told me that Tom was the only person that I could depend on.
(2)Chinais a country which has a long history.
(1) His mother, who loves him very much, is strict with him.
(2)China, which was founded in 1949, is becoming more and more powerful.
(1) His brother who is now a doctor always encourages him to go to college.
(2) His brother, who is now a doctor, always encourages him to go to college.
1．当先行词是anything, everything, nothing (something除外), few, all, none, little, some等代词时，或者是由every, any, all, some, no, little, few, much等修饰时
(1) Have you taken down everything that Mr. Li has said?
(2) There seems to be nothing that seems impossible for him in the world.
(3) All that can be done has been done.
(4) There is little that I can do for you.
(4) Any man that/.who has a sense of duty won”t do such a thing.
(1) The first place that they visited in London was the Big Ben.
(1) This is the best film that I have seen.
4.当先行词被the very, the only修饰时
(1) This is the very dictionary that I want to buy,
(2) After the fire in his house, the old car is the only thing that he owned.
(3) Wang Hua is the only person in our school who will attend the meeting/
(1) Who is the man that is standing there?
(2) Which is the T-shirt that fits me most?
(1) Can you remember the scientist and his theory that we have learned?
what was the name of the war in theUSAwhich lasted 5 years?
2. 当先行词是one, ones, anyone,等时用who; those做先行词时，指人用who, 指物用which
Those who want to go to the Great Wall sign up here.
He who has never been to the Great Wall is not a true man.
3. 介词+which, whom
(1) He married her, as/which was natural
(2) He was honest, as/which we can see.
(1) As is known to all,Chinais a developing country.
(2) He is from the south, as we can see from his accent.
(3) John, as you know, is a famous writer.
(4) He has been to Paris more than several times, which I don”t believe.
(5) Tom was always late for school, which made his teacher angry.
3.当先行次受such, the same修饰时，常用as
(1) I have never heard such a story as he tells.
(2) He is not such a fool as he looks.
(3) This is the same book as I lost last week.
(4) She wore the same dress that she wore at Mary”s wedding.
(5) She wore the same dress as her young sister wore.
（三）以the way为先行词的定语从句通常由in which, that引导，而且通常可以省略。
(1) The way in which/ that/./ he answered the question was surprising.
but可被看作关系代词，引导定语从句，在从句中作主语，意义上相当于 who not或that not，即用在否定词或具有否定意义的词后，构成双重否定。如：1）There is no mother but loves her children．没有不爱自己孩子的母亲。 2）There was no one present but knew the story already．在场的人都知道这个故事。
(3) There are very few but understand his idea. ( but= who don”t )
(1) The plane that has just taken off is for London.定语从句
(2) The fact that he has been dead is clear.同位于从句
2．定语从句由关系代词或者关系副词引导，关系词在句中充当成分，有时可以省略；同位语从句主要由that引导，在句中一般不做成分；句子也可以由when, where, how, why, whether, what等词引导，充当成分
(1) The news he told me is true.
(2) The news that he has just died is true.
3) The problem that we are facing now is how we can collect so much money.定语
(4) The problem how we can collect so much money is difficult to solve.
(1) The idea that we could ask the teacher for advice is wonderful.
(2) The idea was that we could ask the teacher for advice.
(3) The fact that the earth moves around the earth is known to all.同位语
(4) The fact is that the earth moves around the earth.