5、关系代词that和which的区别（1)相同点这两个关系代词引导定语从句时，都可以指物；在从句中都可作主语或宾语；作宾语时都可省略The train that ( which ) has just left is for Shanghai.刚开的那列火车是去上海的作主语)The film that(which) we saw last night is wonderful.我们昨天晚上看的电影好极了作宾语，可省略)（2）用that，不用which的情况①当先行词是不定代词或被它们修饰时all, everything, nothing, something, anything, little等不定代词时（something之后也可用which）To get the job started, all that I need is your permission.要开始工作，我所需要的是你的许可Is there anything that I can do for you?有什么要我做的事吗?He answered few questions that the teacher asked.他几乎没有回答老师的那些问题。
②当先行词被形容词最高级或序数词修饰时This was one of the most interesting books that were sold in this book store.这是这家书店售出的最有趣的书之一The first thing that should be done is to get some food.该做的第一件事是弄点吃的③当先行词有the very，the only，the same等修饰时That’s the only thing that we can do now.目前我们只能这样了Those are the very words that he used.那就是他的原话④当先行词是一个既指人又指物的并列词组时They were talking about the persons and things that they saw in the factory.他们在谈论在工厂里看到的人和事They talked for about half an hour of things and persons that they remembered in the school. 他们聊起他们所能记得起的学校里的人和事来，聊了约半个钟头。
⑤当关系代词在定语从句中作表语时China is not the country that it was.中国已经不是过去的中国了⑥当要避免与疑问词which重复时Which is the car that was made in Beijing?哪辆车是北京制造的?⑦当先行词为the way, the time, the period等时，关系代词常用that，但通常被省略I don't like the way(that)you speak to her.我不喜欢你对她说话的方式3）用which，不用that的情况①引导非限制性定语从句Football, which is an interesting game, is played all over the world.全世界都踢足球，它是一项有趣的运动Carol said the work would be done by October, which personally I doubt very much. 卡罗尔说这项工作将在十月前做，对此我个人表示怀疑Dorothy was always speaking highly of her role in the play, which ,of course, made the others unhappy. 桃乐茜总是吹嘘她在戏剧中的角色，这当然使别人不高兴。
②直接放在介词后作宾语时Language is the most important tool without which people can't communicate with each other.语言是最重要的工具，没有它，人们便无法交流巧记that和which的区别：that，which可互换，下列请况勿照办；that情况比较多，不妨对你说一说；不定代词这路货，全用that准没错；先行词前被限制，千万不要用which；要用which别着急，介词提前逗隔离6、关系代词who与that的区别（1）当先行词是he、people、those等时，引导词常用whoHe who does not reach the Great Wall is not a true man. 不到长城非好汉Those who are for me, put up your hands. 同意我的人请举手I'll never forget the people who have helped me. 我将永远不会忘记那些帮助过我的人2）当引导词作定语从句的表语时常用thatShe isn't the little girl that she used to be. 她再也不是过去的那个小姑娘了。
He is the man that I asked for help yesterday.他就是我昨天求助的人7、as的用法（1）as引导限制性定语从句通常构成such...as或the same...as固定搭配，as在从句中可作主语、表语或宾语 I should like to use the same tool as you used yesterday.我想用你昨天使用的那种工具作宾语)Many of the sports were the same as they are now.过去的许多运动项目同现在的一样作表语)Don’t read such books as are not worth reading. Read such books as you can understand.不要读那些不值得读的书，只去读那些你能读懂的书就可以了He lent me as much money as he had.她把所有的钱借给了我Repeat this as often as is necessary.根据需要反复这样做作主语)（2）such…that…与such…as“such…that…”表示“如此……以致……”的意思，用来引导一个结果状语从句；而“such…as…”表“像……这样的……”的意思，用来引导定语从句，as在从句中充当主、宾或表语等。
He is such an honest man that we respect him.他是一个如此诚实的人以至于我们都尊敬他He is such an honest man as we respect.他像我们所尊敬的这种诚实的人3）the same…that…与the same as“the same…that…”表同一人或物，而“the same…as…”表同种类的东西试比较下列两个句子：This is the same book that I lost.这就是我丢失那本书指同一本书）This is the same book as I lost.这本书跟我丢失那本书一模一样并不是原来的那一本）（4）as 引导非限制性定语从句as作关系代词，还可用来引导非限制性定语从句，可以用来代替一个句子或单词，as引导的句子可放在句首、句末或句中The moon, as is known to everybody, travels round the earth once every month.As is known to everybody, the moon travels round the earth once every month.The moon travels round the earth once every month, as is known to everybody.众所周知，月球一月绕地球一周。
8、but 的用法but既可指人，又可指物，常在定语从句中充当主语but 本身含“否定”的意思，其作用相当于“that/which/who…not”它前面的主句必须有“否定”的词(如no, not, little, few, hardly等)but引导的肯定定语从句和否定的主句连用，通过双重否定达到强烈肯定的效果There is no mother but loves her own children.(=There is no mother that/who doesn’t love her children.)没有不爱自己子女的母亲There were few people but were hurt.(= There were few people who/that were not hurt.)几乎没有人不受伤9、than的用法than既可指人，又可指物，可作关系代词来引导定语从句，than前通常有比较级的词Don’t give children more money than is needed.给孩子们的钱不要超过所需He has got more than he asked for.他所得到的比他所要求的还要多。
Fewer friends than we had expected came to our evening party.来参加晚会的朋友比我们预料的还要少四、关系副词英语中的关系副词有where，when，why等1、when的用法when指时间，修饰表时间的先行词，在定语从何中作时间状语July and August are the months when the weather is hot. 七八月是天气很热的月份He came last night when I was out. 他昨晚来时，我出去了Do you remember one afternoon ten years ago when I came to your house and borrowed a necklace of yours?你还记得十年前的一个下午，我到你家借项链的事吗?2、where的用法where指地点，修饰表地点的先行词，在定语从句中作地点状语After living in Paris for fifty years he returned to the small town where he grew up as a child.在巴黎住了五十年后，他回到他童年时生活的小城镇。
I can still remember the sitting-room where my mother and I used to sit in the evening.我还记得那间我妈妈和我晚上常坐在一起的起居室She will go home where she can rest. 她要回家了，在家里她可以休息One morning, an elephant was led down the road where they stood. 一天上午，有人赶着一头象沿着他们站立的那条路走过来注意：先行词为表示时间、地点的名词时，关系词不一定都用when或where如果关系词在定语从句中作主语或宾语，就要用关系代词whch或thatThis is the factory that/which we visited last year.这是我们去年参观的那家工厂I won't forget the time that we spent in the countryside.我永远不会忘记我在农村度过的那段时光3、why的用法why指原因，修饰名词reason，在定语从句中作原因状语This is the reason why he did so. 这就是他这样做了的理由。
Do you know the reason why he left early?你知道他为什么早走吗？巧记定语从句的用法主句型，从句型，两种句子要完整从句紧靠先行词，系词引导要弄清定人用who或whom，定物which当先用关系代词有that，定人定物有本领定时间要用when，定地点where行关系代(副)词作成分，唯作宾语可以省五、“介词＋关系代词”用法1、介词+which在定语从句中分别作时间、地点和原因状语介词+which在关系分句中分别作时间，地点和原因状语，代替相应的关系副词when，where和whyI still remember the day on which (=when)I first came to school.我仍然记得初来学校的那一天The factory in which (=where) I work is a large one.我工作的工厂是一个大厂子This is the reason for which(=why)he was put in prison.这就是他为什么被关起来的原因In the office I never seem to have time until after 5:30 p.m., by which time many people have gone home. 在办公室里，我好像知道五点半从有时间，在此前很多人都已回家了。
注意：关系代词that在定语从句中作介词的宾语时，介词不能放在它的前面，只能放在从句中有关动词的后面The village that she lives in is 100 metres away. 她住在100米远的村庄里2、介词+which(指物)/whom(指人)在定语从句中作地点状语介词+which(指物)/whom(指人)在关系分句中作地点状语，表示存在关系，关系分句主谓常须倒置They arrived at a farm house in front of which sat a small boy.他们来到一处农舍，前边坐着一个小孩I saw a man, on the head of whom stood a bird.我看见一个人，他的头上站着一只鸟3、不定代词或数词+of+which(指物)/whom(指人)，在定语从句中作主语不定代词或数词+of+which(指物)/whom(指人)，在关系分句中作主语，说明整体中的部分China has a lot of islands, one of which is Taiwan.中国有许多岛屿，其中之一是台湾There are a lot of students here，none of whom like the film.这里有许多学生，他们之中无人喜欢这个电影。
4、介词+which(指物)/whom(指人)，在关系分句中作目的、方式或地点状语这种结构中的介词一般受动词或介词后的名词所制约Could you tell me for whom you've bought this coat?你能告诉我这件衣服是给谁买的吗?The rat is digging a tunnel through which it can reach the field to get food.这只老鼠正在挖洞，通过这条洞它能到田里搞吃的The man, from whom I learned the news, is an engineer.这人是一位工程师，我是从他那里得到这消息的5、介词+which(指物)/whom(指人)，用于被动结构的关系分句中，作状语，说明动作的发出者The wolf by which the sheep was killed was shot. 伤害羊的那只狼被打死了The man by whom the wolf was shot was a good hunter. 打死狼的那人是一个好猎手6、名词+of which，代替whose+名词，在关系分句中作定语。
He paid the boy $10 for washing ten windows, most of which hadn't been cleaned for at least a year.他给了那个男孩10美元让她擦十扇窗户，大部分窗户至少一年没擦了I saw some trees, the leaves of which (=whose leaves)were black with disease.我看见一些树，它们的叶子因生病而发黑He mentioned a book, the title of which (=whose title )I've forgotten.他提到一本书，书的名我忘了7、介词+which(指物)/whose(指人)，修饰后边的名词It rained all night and all day, during which time the ship broke into pieces.雨下了一天一夜，就在这期间轮船撞碎了The driver was the man from whose room she had stolen the maps.司机就是她从他的房间偷走地图的那个人。
比较：介词+which+不定式此种用法多见于正式文体中，相当于一个带有主语和谓语的定语从句She had only 1.87 with which to buy(=she could buy)Jim, her husband, a present.她只有一元八角七分钱，用这些钱给他的丈夫吉姆买一件礼物At last he had something about which to write (=he could write) home. 他终于有给家写信的内容了。