英语语法.docx

高中英语备考:英语中反义疑问句的用法1. 当陈述部分的主语是I，而句子又用来征询对方的意见时，附加疑问句中的主语用you。如：I find English very interesting, dont you? I dont like that film, do you?2. 当陈述部分的主语是everybody, everyone, someone, nobody, no one, somebody等合成代词时，附加疑问句中的主语通常用they。但亦可用he，尤其是nobody, no one等作主语，具有否定概念时。如：Somebody phoned while I was out, didnt they? Everyone enjoyed the party, didnt they?3. 当陈述部分的主语是不定代词everything, nothing, anything, something时，附加 疑问句中的主语一般用it，不用they。如：Everything seems all right now, doesnt it? Nothing is kept in good order, is it?4. 当陈述部分的主语是指示代词this, that或these, those时，附加疑问句中的主语分别用it和they。如：This is important, isnt it? These are your friends Tom and Jack, arent they?5. 如果陈述部分是以代词one作主语，附加疑问句中的主语在正式场合用one，非正式场合用you,在美国英语中，在非正式场合还可以用he。如：One cant be too careful, can one?或can you? One should do his duty, shouldnt he?6. 如果陈述部分用Im结构，附加疑问部分一般用arent I。如：I am strong and healthy arent I。7. 当陈述句为there be结构时，附加疑问句中的主语也用there。如：Theres no help for it, is there? Theres something wrong, isnt there?8. 陈述部分带有seldom, hardly, never, rarely, few, little,nowhere, nothing等否定词或半否定词时，附加疑问部分的动词用肯定形式。如：Bob rarely got drunk, did he?Few people know him, do they?如果陈述部分的否定词带有否定前缀，那么，该陈述部分作肯定处理，附加疑问部分一般仍用否定形式。如：He wasunsuccessful, wasnt he? Tom dislikes the book, doesnt he?9. 当陈述部分为主从复合句时，附加疑问部分一般应与主句的主语和谓语动词保持对应关系。如：She says that I did it, doesnt she? I told them not everybody could do it ,didnt I?但当陈述部分的主语是I，谓语是think, believe, suppose, expect这类动词时，附加疑问部分则往往与从句中的主语和谓语动词保持对应关系，但要注意否定的转移。I suppose that hes serious isnt he? I dont think she cares, does she?10. 当陈述部分是并列句，附加疑问句则需和就近的分句的主语和谓语一致。如：Xiao Lin has been writing letters all afternoon but he should finish them now, shouldnt he?11. 在由“祈使句+附加疑问”构成的附加疑问句中，附加疑问部分一般用will you, wont you, would you,有时也可用can you, cant you, why dont you, could you等。如：Dont open the door, will you?Give me some cigarettes, can you?但是，以lets开头的祈使句，附加疑问部分用shall we;以let us开头的祈使句，如果含义是allow us，不包括听话人在内，疑问部分用will you。如：Lets have a basketball match this afternoon, shall we?12. 当陈述部分带有情态动词must表示“必须”时，疑问部分用mustnt。如：You must work hard next term, mustnt you? I must answer the letter, mustnt I?但若表推测这层含义时，不能用must，而要根据陈述部分的不定式结构(即must之后的动词)以及含义采用相应的动词形式。如：You must have made a mistake,havent you?They must have seen the film last week, didnt they?13. 当陈述部分含有情态动词used to时，疑问部分可用usednt或didnt。如：The old man used to smoke, didnt he?或usednt he?14. 当陈述部分带有情态动词ought to时，疑问部分用oughtnt或shouldnt。如：We ought to read this book, oughtnt we?或shouldnt we?15. 当陈述部分含有had better时，疑问部分用had。如：Youd better finish your homework now, hadnt you?16. 感叹句后的附加疑问句的谓语动词需用be的现在时，且常用否定形式。如：What a clever boy, isnt he? What a lovely day, isnt it?17. 陈述句子中的主语为动词不定式短语、动名词短语或其他短语时，疑问部分的主语通常用it。如：Learning how to repair motors takes a long time, doesnt it?Between six and seven will suit you, wont it?18. 在口语和非正式文体中，为了加强语气，只是表示某种惊奇、怀疑、反感、讽刺等感情而并不是为了寻求回答，这时前后两部分的肯定、否定是一致的。如：Oh, he is a writer, is he? Youll not go, wont you?19. 陈述句中的谓语动词是wish，表示愿望时用may，且用肯定形式。如：I wish to have a chance to learn English, may I?20. 当陈述部分带有表示“所有”含义的动词have(has)时，疑问部分既可用have形式，也可用do形式。如：You have a new bike,havent you(或dont you)?动词时态:过去进行时用法的五个注意事项一、注意过去进行的基本用法过去进行时主要表示过去某一时间正在进行的动作。如：Hefellasleep when he was reading. 他看书时睡着了。We were expecting you yesterday. 我们昨天一直在等你。He was playing while I was studying. 我在做功课时他在玩。二、注意过去进行时表示现在的用法用过去进行时表示现在，主要是为了使语气委婉、客气。如：I was wondering if you could give me a lift. 我不知你能否让我搭一下车。We were hoping you would stay with us. 我们很希望你能跟我们住在一起。How much did you want to spend, sir? 先生，您打算花多少钱？注：一般过去时也有类似用法，但比较而言，用过去进行时显得更客气，更不肯定。三、注意过去进行时表示感情的色彩与现在进行时相似，过去进行时也可表示满意、称赞、惊讶、厌恶等感情的色彩，也通常与 always, forever, continually等副词连用。如：They were always quarrelling. 他们老是吵架。The boy was continually asking questions. 这个男孩子老是问东问西的。四、注意动词be的过去进行时动词be的进行时也可表示过去一时的表现或暂时的状态。比较：He wasfriendly. 他很友好。(指过去长期如此)He was beingfriendly. 他当时显得很友好。(指当时一时的表现)五、注意过去进行时和一般过去时的区别两者的基本差别是过去进行时通常表示一个过去正在进行且尚未完成的动作，而一般过去时则通常表示一个过去已经完成的动作。如：I was reading a book last night. 我昨晚在看书。(不一定看完)I read a book last night. 我昨晚看了一本书。(已经看完)They were building a bridge there. 他们在那里修一座桥。(不一定建成)They built a bridge there. 他们在那儿修了一座桥。(已建成)注：有些动词(如rain, snow, cough, wear, feel, work等)本身并不表示动作完成，这时用两种时态都可以，且含义区别不大：It rained was raining all day yesterday. 昨天下了一天的雨。She didnt feel wasnt feeling well that day. 那天她感到不太舒服。定语从句:考生备考定语从句容易犯的七个错点一、混淆定语从句与并列句请看下面两题：(1) He has two children, and both of _ are abroad.A. them B. which C. whom D. who(2) He has two children, both of _ are abroad.A. them B. which C. whom D. who【分析】第(1)题选A，第(2)题选C。由于第(1)题中用了并列连词and，从而使整个句子为并列句，and后应是一个独立的简单句，所以选A不选C；第(2)题没有并列连词and，both of whom are abroad为非限制性定语从句。二、混淆定语从句与表语(从句)请看下面的试题：(1) Your coat is still _ you left it.A. where B. there C. there where D. the place where【分析】答案选A，where引导的是表语从句(=在的地方)，而不是定语从句。(2) Is thisschool_ your father worked in ten years ago?A. where B. what C. that D. the one【分析】答案选D，thisschool为句子主语，the one 为表语，your father worked in为定语从句。不要误认为this是句子主语，否则school前应加冠词the。比较：Is this theschool_ your father worked in ten years ago?A. where B. what C. that D. the one (选C)Is this theschool_ your father worked ten years ago?A. where B. what C. that D. the one (选A)三、混淆定语从句与状语从句请看下面的试题：(1) I went upstairs _I heard some crying.A. where B. when C. that D. which【分析】答案是B而不是A，when的意思是“当的时候”，引导的是时间状语从句。(upstairs为副词，不宜用作先行词)(2) He is _ a clever boy _ we all like.A. such, that B. such, as C. so, that D. so, as【分析】答案应选B，而不是A。such that (如此以致)用于引导结果状语从句，其中的that不充当句子成分，而suchas中的as为关系代词，用以引导定语从句并在定语从句充当句子成分。上句中第二空之所以选as，是因为它用作动词like宾语。四、误加与关系代词同义的人称代词误：He is a man everyone respects him.正：He is a man everyone respects. 他是一个人人都敬重的人。五、混淆关系代词与关系副词有的同学一看到先行词是表示时间、地点、原因的名词，就认为一定要用关系副词，其实也一定。在此情况下，还要看关系词在定语从句中是用作什么成分，若是用作状语，则用关系副词，若不是用作状语(如用作主语、宾语等)则不能用关系副词，而用关系代词。比较：This is the factory where I want to work. 这就是我想工作的工厂。(work为不及物动词where在从句中用作状语)This is the factory that I want to visit. 这就是我想参观的工厂。(visit为及物动词，that用作visit的宾语)The reason why he cant come is that he is ill. 他没来的是因为他病了。(come为不及物动词，why在定语从句中用作状语)The reason that he put forth is very important. 他提出的理由很重要。(put forth为及物动词，that在定语从句中用作其宾语)六、因逗号误判which有的同学一看见逗号，就以为一定要选which而不选that，但问题是有时根本就不是定语从句：(1) If a book is in English, _ means slow progress for you.A. as B. which C. what D. that(2) When I say two hours, _ includes time for eating. (D19/541)A. as B. which C. what D. that【分析】以上两题均应选that，而不能选which，因为它们根本不是定语从句。之所以选that，是因为句中已有if和when引导的状语从句，逗号后为主句，that为主句主语。七、混淆which与whose两者在定语从句中都可用作定语，区别是：whose 的意思相当于 ones，而 which 的意思则相当于 that 或 this。比较：(1) This is Mary, whose = and her father we met last week.(2) Call again at 11, by which time = and by that time the meeting should be over.虚拟语气:虚拟条件句的三种基本类型条件句有真实条件句和非真实(虚拟)条件句两种。真实条件句所表示的假设是有可能发生的，而非真实条件句则通常表示一种假想，与事实相反或不大可能会发生：If I have time, I will go with them. 假若我有时间，我就同他们去。(陈述语气)If I were you, I would go with them. 假若我是你，我就同他们去。(虚拟语气)一、与现在事实相反若与现在事实相反，条件从句的谓语用过去式(be通常用were)，主句谓语用should (would, could, might)+动词原形：If you took a taxi, youd get there quicker. 如果你坐出租车去，你可以快一点到那里。(但你不坐)If I knew her number I could ring her up. 要是我知道她的电话号码，我就可以给她打电话了。(可惜我不知道)二、与过去事实相反若与过去事实相反，条件从句的谓语用过去完成时(had+过去分词)，主句谓语用“should (would, could, might)+have+过去分词”：If Id left sooner，Id have been on time. 要是我早点动身，我就准时到了。(但我动身太迟了)If we had found him earlier we could have saved his life. 要是我们当时早点找到他的话，我们就可以救活他。(可惜我们找到他太晚了)三、与将来事实相反若与将来事实相反，条件从句的谓语用过去式(be通常用were)，主句谓语用should (would, could, might)+动词原形：If he went, would you go too? 如果他去，你也去吗?(大概他不会去)If I asked him, Im sure hed help us. 如果我向他提出要求，肯定他会帮助我们。(不过我不打算这样做)注：几点特别说明 主句谓语中的should主要用于第一人称后。would, might, could的大致区别是：would表示结果，might表示可能性，could表示能力、允许或可能性。比较：If you tried again you would succeed. 要是你再试一试，你就会成功的。(would表结果)If you tried again you might succeed. 要是你再试一试，你可能会成功的。(might表可能)If you tried again you could succeed. 要是你再试一试，你就能成功了。(could表能力) 条件从句的谓语动词为be时，不管其主语为单数还是复数通常都用were，但在口语或非正式文体中的单数第一人称和第三人称后，也可用was，不过在 If I were you这样的表达中，通常还是以用were为宜。 有时条件从句用would表示愿意：If he would live on with me, I would be his better half. 要是他还愿意跟我过，我仍会做他的妻子。 对于与将来事实相反的情形，请注意以下几点：一是这里说的与将来事实相反，实为对将来情况的推测；二是此用法中的条件从句谓语除用过去式外，有时也用“should+动词原形”(表示可能性极小，常译为“万一”)或“were to+动词原形”(表示与将来事实相反的假设)；三是当条件从句使用“should+动词原形”这样的谓语时，主句谓语除可用“should (would, could, might)+动词原形”这样的虚拟语气外，也可用陈述语气或祈使语气：If it should rain tomorrow, dont expect me. 万一明天下雨，就不要等我了。I should see him, Ill tell him. 万一我见到他，我就告诉他。倒装句:完全倒装的四种主要类型1. here 和there位于句首时的倒装表示地点的here和 there位于句首时，其后用完全倒装形式。这类倒装句的谓语通常是动词be和come, go等表示移动或动态的不及物动词：Heres Tom. 汤姆在这里。 Theres Jim. 吉姆在那儿。Here comes the bus. 公共汽车来了。 There goes the bell. 铃响了。【注意】(1) 以上倒装句中的谓语动词come和go不能用进行时态，即不能说 Here is coming the bus。(2) 若主语为代词，则不倒装：Here I am. 我在这儿。/ 我来了。 Here it comes. 它来了。(3) 其中的动词有时也可能是stand, lie, live等表示状态的动词(表示存在)：There stood a desk against the wall. 靠墙放着一张书桌。Once upon a time there lived a man known by the name of Beef. 从前有个人名叫比夫。2. away和down等位于句首时的倒装地点副词away, down, in, off, out, over, round, up 等位于句首时，其后用完全倒装语序。这类倒装句的谓语通常表示动态的不及物动词：Away went the runners. 赛跑选手们跑远了。Round and round flew theplane. 飞机盘旋着。The door opened and in came Mr Smith. 门开了，史密斯先生进了来。【注意】若主语为人称代词，则不能用倒装：Away he went. 他跑远了。 Down it came. 它掉了下来。3. 状语或表语位于句首时的倒装为了保持句子平衡或使上下文衔接紧密，有时可将状语或表语置于句首，句中主语和谓语完全倒装：Among these people was his friend Jim. 他的朋友吉姆就在这些人当中。By the window sat a young man with a magazine in his hand. 窗户边坐着一个年轻人，手里拿着一本杂志。【注意】在表语置于句首的这类倒装结构中，要注意其中的谓语应与其后的主语保持一致，而不是与位于句首的表语保持一致。比较：In the box was a cat. 箱子里是一只猫。 In the box were some cats. 箱子里是一些猫。4. 分词和不定式置于句首的倒装有时为了强调，可将谓语部分的现在分词、过去分词或不定式置于句首，从而构成倒装：Buried in the sands was an ancient village. 一个古老的村庄被埋在这沙土之中。Standing beside the table was his wife. 站在桌旁的是他的妻子。To be carefully considered are the following questions. 下列问题要仔细考虑。it的用法:it用作形式主语的用法一、基本用法当不定式、动名词、从句等用作主语时，避免头重脚轻，通常在句首使用形式主语it，而把真正的主语放在句子末尾：Is it necessary to tell his father everything? 有必要把这一切都告诉他父亲吗?Its no good sitting up too late. 熬夜没有好处。It is quite clear that he has read the book. 很显然，他读过这本书。It doesnt matter what he says. 他说什么没关系。二、几种特殊的形式主语(1) 用作动词look, seem, appear, happen, occur, follow等的主语(后接that从句或as if从句)：It seems as if it is going to rain. 看来要下雨了。It seems that he knows everything. 他好像什么都知道。It (so) happened that I had no money with me. 碰巧我没带钱。From thiswitnessit follows that he must beguilty. 根据该证人的证词判断，他一定有罪。(2) 当系表结构后接有if 或when引出的状语从句时，通常在系表结构前使用形式主语表示说话人对某情况的看法：It was a great surprise to me when he did a thing like that. 他这样做使我很吃惊。It would be a tragedy if anything went wrong. 如果出了什么事就是一个悲剧。(3) 用于其他固定句型，如if it were not for(若不是因为)，its time that(该了)等。三、误用形式主语的几种情形(1) 在该用it作形式主语的地方而误用其他词：Is _ necessary to tell his father everything?A. it B. that C. what D. he此题的正确答案应是A(it用作形式主语)，而不能选D。(2) 在不该用形式主语的地方而误用形式主语：_ must be something wrong with the machine.A. There B. It C. He D. That此题应选A，为there be句型与情态动词must连用的情形。比较以下两组句子：_ is known to us all, the earth turns around the sun._ is known to us all that the earth turns around the sun.A. It B. Which C. As D. That前一句填C，as用以引导一个非限制性定语从句；后一句填A，it为形式主语，真正的主语是其后的that从句。_ is difficult topersuadeher to stay. _ is difficult is topersuadeher to stay.A. It B. What C. He D. That前一句填A，it为形式主语；后一句填B，what用以引导主语从句。注意后一句比前一句在不定式前多了个is。比较级:英语比较级和最高级前使用冠词的规律一、基本规律在通常情况下，英语比较级前不用冠词，形容词最高级前用定冠词，副词最高级前可以用定冠词，也可以不用。如：This homework is all right but you could do it better. 这份家庭作业还算可以，其实你可以做得更好。That is the best way topreventsuch a thing happening again. 这是防止这样的事再次发生的最好办法。The boss praised those who had worked (the) hardest. 老板表扬了那些工作最努力的人。二、比较级前冠词使用规律比较级前通常不用冠词，但有时也用，这主要见于以下情形：1. 当比较级后接名词时，比较级前可能用冠词，此时的冠词不是修饰比较级，而是修饰其后的名词。如：Which of them is the better choice?Well, its hard to tell. 他们谁是更合适的人选?嗯，这很难说。Some of the more time-consuming jobs can now be done by machines. 有些更费时间的工作现在可以用机器做了.但是，若受比较级修饰的名词为表泛指的复数名词或不可数名词，则仍不用冠词。如：Hes got more money than the rest of us (put) together. 他的钱比我们大家的加在一起的总数还多。Fewer people write with their left hand than with their right. 用左手写字的人比用右手的少。2. 当要特指两者中“较(更)”时，比较级前通常要带定冠词，此时可视为比较级后省略了有关的名词或代词one，即定冠词实为修饰被省略的名词或代词one。如：Which of the two methods is the better? 这两种方法哪一种更好?Of the two possibilities, this is more likely than that. 两个可能性中，后者比前者更可能。3. 在比较级前用the表示程度(通常有表示原因、理由或条件的短语或从句)。如：Hes had a holiday and looks the better for it. 他度假之后，气色好多了。I love him all the more for his faults. 正因为他这些缺点，所以我越发爱他。4. 用于“the+比较级，the+比较级”，表示“越越”。如：The younger you are, the easier it is to learn. 年纪越轻，学习越容易。The better I know her, the more Iadmireher. 我对她越了解，我就越爱慕她。The more money you make, the more you spend. 你挣的钱越多，花的钱也越多。5. 当by far用于修饰比较级且置于其前时，比较级前要用the。如：He is by far the cleverer than her. 他比她聪明得多。Its quicker by far to go by train. 坐火车去要快得多。注：与比较级连用，通常要放在比较级之后，若放在比较级前，则比较级通常应带有冠词。如：He is cleverer by far than her. Its by far the quicker to go by train.三、最高级前冠词使用规律1. 在形容词最高级前通常用the。如：Hes the best teacher even though he has the least experience. 他尽管经验最少，但教得最好。2. 当最高级形容词用作表语(尤其是用于which后)且不带比较范围时，the有时(尤其是非正式场合)可以省略。如：Which of the boys is (the) strongest? 这些男孩子当中哪个力气最大？但是，当处于表语位置的最高级带有比较范围或带有限定性修饰语时，其前的the通常不能省去。如：This dictionary is the best I could find. 这是我能找到的最好的词典。He was the strongest of all the students. 他是所有学生中最强壮的。3. 当most表示“非常”时，若其后形容词所修饰的名词为单数可数且表示泛指意义，那么其前用不定冠词而不用定冠词。如：I had a mostunpleasanttime at thedentists. 我在牙医那里受了大罪。She is a mostmysteriousperson. 她是一个非常神秘的人。4. 当要对同一个人或事物在不同情况下进行对比时，处于表语位置的最高级形容词前不能加the。如：Its safest to go by bus. 坐公共汽车去最安全。Vegetables are best when they are fresh. 蔬菜新鲜时最好吃。比较：Hes busiest on Sunday. 他星期天最忙。(他与自己平时比)Hes the busiest of all the people here. 他是这儿所有人当中最忙的。(他与别人比)5. 与形容词的最高级一样，当要对同一个人或事物在不同情况下进行对比时，副词最高级前也不能加the。如：He works hardest when hes doing something for his family. 他为自己家做事时最卖力。比较：Of all the workers, he works (the) hardest. 在所有工人中，他干活最卖力。定语从句定语从句（Attributive Clauses）在句中做定语，修饰一个名词或代词，被修饰的名词,词组或代词即先行词。定语从句通常出现在先行词之后，由关系词（关系代词或关系副词）引出。关系代词有：who, whom, whose, that, which等。关系副词有：when, where, why等。1 关系代词引导的定语从句关系代词所代替的先行词是人或物的名词或代词，并在句中充当主语、宾语、定语等成分。关系代词在定语从句中作主语时，从句谓语动词的人称和数要和先行词保持一致。1）who, whom, that 这些词代替的先行词是人的名词或代词，在从句中所起作用如下： Is he the man who/that wants to see you? 他就是你想见的人吗？（who/that在从句中作主语） He is the man whom/ that I saw yesterday. 他就是我昨天见的那个人。（whom/that在从句中作宾语）2) Whose 用来指人或物，(只用作定语, 若指物，它还可以同of which互换）, 例如： They rushed over to help the man whose car had broken down. 那人车坏了，大家都跑过去帮忙。Please pass me the book whose (of which) cover is green.请递给我那本绿皮的书。3）which, that 它们所代替的先行词是事物的名词或代词，在从句中可作主语、宾语等，例如：A prosperity which / that had never been seen before appears in the countryside. 农村出现了前所未有的繁荣。（which / that在句中作宾语）The package (which / that) you are carrying is about to come unwrapped. 你拿的包快散了。(which / that在句中作宾语）2 关系副词引导的定语从句关系副词可代替的先行词是时间、地点或理由的名词，在从句中作状语。1）when, where, why 关系副词when, where, why的含义相当于介词+ which结构，因此常常和介词+ which结构交替使用，例如： 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？2）that代替关系副词 that可以用于表示时间、地点、方式、理由的名词后取代when, where, why和介词+ which引导的定语从句，在口语中that常被省略，例如： His father died the year (that / when / in which) he was born.他父亲在他出生那年逝世了。 He is unlikely to find the place (that / where / in which) he lived forty years ago. 他不大可能找到他四十年前居住过的地方3 判断关系代词与关系副词方法一： 用关系代词，还是关系副词完全取决于从句中的谓语动词。及物动词后面无宾语，就必须要求用关系代词；而不及物动词则要求用关系副词。例如： This is the mountain village where I stayed last year. Ill never forget the days when I worked together with you. 判断改错（注：先显示题，再显示答案，横线；用不同的颜色表示出。） （错） This is the mountain village where I visited last year. （错） I will never forget the days when I spent in the countryside. （对） This is the mountain village (which) I visited last year. （对） Ill never forget the days (which) I spent in the countryside.习惯上总把表地点或时间的名词与关系副词 where, when联系在一起。此两题错在关系词的误用上。 方法二： 准确判断先行词在定语从句中的成分(主、谓、宾、定、状)，也能正确选择出关系代词/关系副词。例1. Is this museum _ you visited a few days age? A. whereB. that C. on which D. the one例2. Is this the museum _ the exhibition was held. A. whereB. that C. on whichD. the one答案：例1 D，例2 A例1变为肯定句： This museum is _ you visited a few days ago.例2变为肯定句： This is the museum _ the exhibition was held.在句1中，所缺部分为宾语，而where, that, on which都不能起到宾语的作用，只有the one既做了主句的表语，又可做从句的宾语，可以省略关系代词，所以应选D。而句2中, 主、谓、宾俱全，从句部分为句子的状语表地点，既可用副词where，又因 in the museum词组，可用介词in + which 引导地点状语。而此题中，介词on 用的不对，所以选A。关系词的选择依据在从句中所做的成分，先行词在从句中做主、定、宾语时，选择关系代词 (who, whom, that, which, whose)； 先行词在从句中做状语时，应选择关系副词 ( where 地点状语，when 时间状语，why 原因状语) 。4 限制性和非限制性定语从句1) 定语从句有限制性和非限制性两种。限制性定语从句是先行词不可缺少的部分，去掉它主句意思往往不明确；非限制性定语从句是先行词的附加说明，去掉了也不会影响主句的意思，它与主句之间通常用逗号分开，例如：This is the house which we bought last month.这是我们上个月买的那幢房子。（限制性）The house, which we bought last month, is very nice.这幢房子很漂亮，是我们上个月买的。（非限制性）2) 当先行词是专有名词或物主代词和指示代词所修饰时，其后的定语从句通常是非限制性的，例如：Charles Smith, who was my former teacher, retired last year. 查理史密斯去年退休了，他曾经是我的老师。My house, which I bought last year, has got a lovely garden.我去年买的的那幢房子带着个漂亮的花园。This novel, which I have read three times, is very touching. 这本小说很动人，我已经读了三遍。3) 非限制性定语从句还能将整个主句作为先行词, 对其进行修饰, 这时从句谓语动词要用第三人称单数，例如：He seems not to have grasped what I meant, which greatly upsets me. 他似乎没抓住我的意思，这使我心烦。Liquid water changes to vapor, which is called evaporation. 液态水变为蒸汽，这就叫做蒸发。说明：关系代词that和关系副词why不能引导非限制性定语从句。9 关系代词that 的用法1）不用that的情