1、Unit 8 主从复合句 语法精讲 由一个主句和一个或一个以上的从句构成的句子叫主从复合句。主 句为句子的主体，从句只是充当句子的一个成分。初中阶段，根据从句 在句子中的作用，可以把它分为宾语从句、状语从句和定语从句。 考点1 宾语从句 在复合句中用作宾语的从句称作宾语从句。它在复合句中作主句谓 语动词、介词或某些形容词的宾语。 I know the man. 我认识这个人。（名词the man作know的宾语） I know that he is a policeman. 我知道他是一名警察。 （that he is a policeman作know的宾语从句） 1.引导宾语从句的连词或代词
2、 （1）陈述句充当宾语从句时，用that引导，that无词义，在口语或 非正式文体中常省略。 My teacher said（that）I was a good boy. 老师说我是个好男孩。 I am sure（that）he will succeed. 我确定他将会成功。 （2）如果宾语从句原来是特殊疑问句，只需用原来的疑问词引 导，但应注意原疑问语序要变为陈述语序。 What is she doing? Can you tell me? 这两句话可以合为一个宾语从句： Can you tell me what she is doing? 你能告诉我她在做什么吗？ （3）当由一般疑问句充当
3、宾语从句时，用if或whether引导，意 为“是否”。 Is Jim a good student? I dont know. 这两句话可以合为一个宾语从句： I dont know if/whether Jim is a good student. 我不知道吉姆是否是一个好学生。 注意 只能用whether不用if 的三种情况 一般情况下if 和whether可以互换，但以下三种情况只能用 whether： 与or not连用时只能用whether，不能用if： He asked me whether or not I was coming. 他问我是否会来。 Let me know wh
4、ether you can come or not. 让我知道你是否会来。 在介词之后，只能用whether，不能用if： It depends on whether it is going to rain. 它取决于是否会下雨。 I worry about whether I hurt her feelings. 我担心我是否伤害了她的感情。 在不定式之前，只能用whether，不能用if： We havent decided whether to go there. 我们还没有决定是否要去那里。 I dont know whether to accept or refuse it. 我不知
5、道是否该接受它。 2.宾语从句的语序 宾语从句的语序必须是陈述句语序，可总结归纳为下表： 3.宾语从句的时态 宾语从句与主句的时态要相互呼应。 （1）如果主句的时态是一般现在时，宾语从句的时态根据具体情 况来确定，几乎可以是任意时态。 I dont think（that）you are right. 我认为你是不对的。 Please tell us where well go fishing tomorrow. 请告诉我明天我们要到哪里去钓鱼。 Do you know when Mr.Smith moved here? 你知道史密斯先生是什么时候搬到这里的吗？ （2）如果主句的时态是一般过去时
6、，宾语从句只能用相应的过去 时态（一般过去时、过去进行时、过去将来时、过去完成时）。 He told me that he was born in Beijing in 1992. 他告诉我说他1992年出生在北京。 He said that he would go back to the U.S.soon. 他说他很快就回美国。 注意 当从句说明的是一般真理、客观事实、自然现象、名言时，不管 主句用什么时态，从句都用一般现在时。 Dad told us that it is better to do than to say. 爸爸告诉我们行胜于言。 He told the boy that
7、three and three is six. 他告诉这个男孩3+3=6。 Could you tell me where the bookshop is? 你能告诉我书店在哪里吗？ 考点2 状语从句 用来修饰主句中的动词、副词和形容词的从句叫状语从句。根据其 含义状语从句可分为时间状语从句、地点状语从句、条件状语从句、原 因状语从句、目的状语从句、结果状语从句、让步状语从句、比较状语 从句、方式状语从句。 1.时间状语从句 时间状语从句在句中充当时间状语，常用when, as, while, whenever, before, after,since, till, until, as soo
8、n as, once等连词来引导。 While he was doing his homework, the telephone rang. 他正在做家庭作业时，电话铃响了。 After he finished middle school, he went abroad. 上完中学后，他就出国了。 As soon as I arrive, Ill call you. 我一到达就会给你打电话。 2.地点状语从句 地点状语从句在句中充当地点状语，常由where, wherever来引导。 Go wherever you like. 去任何你喜欢的地方。 Youd better stay where
9、 you are.Ill find you. 你最好待在原处，我去找你。 3.条件状语从句 条件状语从句在句中充当条件状语，通常由if, unless, as/so long as 引导。 If you go to the party, you will have a good time. 如果你去聚会的话，你会过得很愉快。 Dont leave the building unless I tell you to. 不要离开这个建筑物，除非我告诉你那样做。 注意 “祈使句+ and（or）+陈述句”在意思上相当于一个带有条件状 语从句的复合句。 Hurry up, or youll be la
10、te.= If you dont hurry up, youll be late. 快点，要不然你就会迟到。 Study hard and you will pass the exam.=If you study hard, you will pass the exam. 如果你努力学习，就会通过这次考试。 4.原因状语从句 原因状语从句在句中充当原因状语，通常由 because, since, as, for, now that引导。 He didnt come to school because he was ill. 他没有来学校因为他病了。 Since you cant answer
11、the question, Ill ask someone else. 既然你不能回答这个问题，我将问问其他人。 注意 because和so不能同用在一个句子里。 5.目的状语从句 目的状语从句在句中充当目的状语，通常由 in order that, so that引 导。 I got up early so that I could catch the first train. 我早起以便能赶上最早一班火车。 6.结果状语从句 结果状语从句在句中充当结果状语，通常由so.that, such.that引 导。在该结构中，被修饰部分的核心词如果为名词，需要用such；如果 被修饰的词为形容词或
12、副词，需要用so；如果被修饰的名词前被表 示“多”或“少”的词（many, much, few, little）修饰时，需要使用so，不用 such。 He is so poor that he cant buy a bike for his son. 他是如此贫穷以至于不能为儿子买辆自行车。 John has made so much progress that the teacher is very satisfied with him. 约翰取得了这么大的进步，老师对他非常满意。 （progress被much修饰，故用so） John has made such great progre
13、ss that the teacher is very satisfied with him. 约翰取得了这么大的进步，老师对他非常满意。 （progress被great修饰，故用such） I have never seen such little sheep that I feel pleasantly surprised. 我从未见过这么小的绵羊，所以我感到很惊喜。 （little意为“小”而非“少”，故仍用such） 7.让步状语从句 让步状语从句在句中充当让步状语，通常由though, although, even if, even though,however, whatever,
14、 as等连词引导。 Though he is young, he knows a lot. 尽管他很年轻，他知道很多事。 While I understand what you say, I cant agree with you. 虽然我理解你的意思，但我还是不能赞同你。 Whatever you plan to do, Im behind you.= No matter what you plan to do, Im behind you. 无论你打算做什么，我都支持你。（whatever引导让步状语从句， 可用no matter what替换） 注意 as和though引导的让步状语从句
15、 as和though都可以引导让步状语从句，不同的是，as引导让步状 语从句时，从句需倒装，though引导让步状语从句一般不用倒装，但 也有代替as倒装的情况。as和though引导倒装的让步状语从句时，通 常需要把名词（通常不加冠词）、形容词、副词、动词原形提前，再 加as或though及其他成分。 Young as he is, he knows a lot. 尽管他很年轻，他知道很多事。 Child as he is, Jack behaves like an adult. 尽管杰克还是个孩子，但他表现得像个大人。 Try as he did, Mark failed to move
16、away the big stone. 尽管尽力了，但是马克仍然搬不动这块大石头。 Hard though he studied, he failed the math examination. 尽管他学习很刻苦，但还是没能通过数学考试。 8.比较状语从句 比较状语从句在句中充当比较状语，通常由than, as.as.来引导。 Tom is nine years older than I am. 汤姆比我大九岁。 Buying a new bike is sometimes as cheap as repairing the old one is. 有时候买一辆新自行车和修一辆旧自行车一样便宜
17、。 9.方式状语从句 方式状语从句在句中充当方式状语，通常由as, as if/though来引导。 Do as Romans do. 入乡随俗。 He behaved as if nothing had happened. 他表现得好像什么事都没有发生过似的。 考点3 定语从句 在复合句中，用来修饰某一名词或代词的从句称作定语从句。被定 语从句所修饰的名词或代词称作先行词，定语从句必须放在先行词之 后，对先行词起修饰限定作用。定语从句也可以理解为在主句中充当定 语的从句。 定语从句的引导词有关系代词that, which, who（whom, whose）和 关系副词where,when,
18、why两种。关系词常有三个作用：引导定语从句、 指代先行词、在定语从句中充当某一成分。 1.关系代词引导的定语从句 （1）如果先行词是表示人的名词或代词，关系代词应用 who（whom, whose）或that。 This is Xiao Wang who/that gave us a talk yesterday. （who/that在从句中作主语） 这就是昨天给我们作报告的小王。 The man whom/that you saw last week has left the town. （whom/that在从句中作宾语） 上周你看见的那个人已离开了城镇。 I know the woma
19、n whose husband is a doctor.（whose在从句中 作定语） 我认识的那个妇女，她的丈夫是个医生。 （2）如果先行词是表示物的名词或代词，则用which或that。 Guilin is a city which/that has a history of over 2000 years. （which/that在从句子中作主语） 桂林是一座具有2000多年历史的城市。 The mooncakes which/that mother cooked taste nice. （which/that在从句中作宾语） 妈妈做的月饼很好吃。 2.关系代词引导定语从句应该注意的几个
20、方面 （1）关系代词在从句中作主语时，从句的谓语动词用单数还是复 数应由先行词决定。 The man who lives downstairs speaks English well. 住在楼下的那个人英语说得很好。 The students who are in Grade Three are going to climb the hill tomorrow. 三年级的学生明天去爬山。 （2）当关系代词在定语从句中作宾语时，往往可以省略。 Mrs.Smith（whom）you met yesterday is a friend of mine. 你昨天碰见的那位史密斯夫人是我的一位朋友。 T
21、his is the book（which）you are looking for. 这是那本你正在找的书。 There are some films（that）Id like to see. 有几部电影我想去看。 注意 关系代词在从句中作介词宾语时，介词可以放在关系代词whom和 which之前（不可放在that之前），此时关系代词不可省略。另外， 若定语从句中的谓语是固定搭配的词组，则其后的介词不可前移至关 系代词之前。 The dictionary which you are looking for is on the desk. 你在寻找的那本词典在桌子上。 （本句中for不可提至wh
22、ich前） The sick man whom she is taking care of is her farther. 她在照顾的病人是她父亲。 （本句中of不可提至whom前） 3.关系代词只能用that不用which的几种情况 （1）当先行词是everything, anything, nothing, none, the one等不定代 词时 He tried to remember everything that the teacher taught him. 他努力记住老师教给他的一切知识。 （2）先行词被序数词或the last修饰时 He was the first stud
23、ent that got to school today. 他是今天第一个到学校的学生。 （3）先行词被all, no, some, any, little, much, few等修饰时 I have done all that he told us to do. 我已完成了他让我们做的所有事情。 （4）先行词被形容词最高级修饰时 He worked out the most difficult problem that I had seen. 他解决了我所见过的最大的难题。 （5）先行词被the very, the only, the same修饰时 I need the same dict
24、ionary that you have. 我需要一本和你那本一样的字典。 （6）先行词是两个或多个分别表示人和物的名词时 He told us many interesting things and persons that we had never heard. 他给我们讲了许多我们从未听说过的有趣的人和事。 （7）主句是以who, which引导的特殊疑问句时 Who is the man that you spoke to just now? 你刚才跟他说话的那个人是谁？ 4.关系副词引导的定语从句 （1）when引导的定语从句 当主句中的先行词（即主句中被后面定语从句修饰的词）是表示
25、时 间意义的名词时，when只能作定语从句的时间状语，放在定语从句句 首。 Ill never forget the time when we worked on the farm. 我将永远不会忘记我们在农场工作的时光。 （2）where引导的定语从句 当主句中的先行词是表示地点意义的名词时，where只能作其所在 的定语从句的地点状语，放在定语从句的句首。 The factory where his father works is in the east of the city. 他父亲工作的工厂在城市东边。 （3）why引导的定语从句 当主句中的先行词表示原因时（the reason），
26、用why引导。 Thats the reason why she left home. 那就是她离家出走的原因。 （why在从句中作原因状语） 注意 并非在时间名词后就一定用关系副词when，在地点名词后就一定 用关系副词where，在表示原因的the reason后就一定用关系副词 why。选用关系副词还是关系代词，关键是看它们在从句中是用作状 语（用关系副词）还是用作主语或宾语（用关系代词）。 I will never forget the day that we spent together last year. 我从不会忘记去年我们一起度过的那一天。（先行词the day在 从句中充当
27、spent的宾语） I will never forget the day when we met each other for the first time. 我从不会忘记我们初次相见的那一天。（先行词the day在从句 中充当时间状语） 专项练习 I.单句填空。 1.While he _（do）his homework, the telephone rang. 2.You should finish your homework _ you go out to play. （before/after） 3.After he finished middle school, he _（go）a
28、broad. 4.I will tell him everything when he _（come）back. 5.I dont know _（if/whether）he will come or not. 6.The English-Chinese dictionary _（that/who）my father bought for me many years ago is still of great help. 7.Jane is one of the students in the class _（who/whose）have ever been to China. 8.Teenag
29、ers like to get something _（that/who）has a great influence on them 9._（Before/Because）he is a newcomer, he has few friends around here. 10.Lu Xun, _（who/whose）real name is Zhou Shuren, wrote lots of novels and essays. II.单项选择。 11.Ill tell Jane about the news _ I see her. A.because B.but C.and D.as s
30、oon as 12.I cant understand this passage _ there are no new words in it. A.if B.because C.though D.an 13.You can do almost anything _ you try hard. A.until B.as long as C.unless D.before 14.Young _ the boy is, he looks calm and determined. A.as B.although C.while D.if 15.I have to take care of my li
31、ttle brother.I cant go to play out _ my mother comes back. A.if B.when C.so that D.unless 16.Can you tell me _ to London? Sure.Next month. A.when you willtravel B.when will youtravel C.when youtravelled D.whendidyoutravel 17.Excuse me, Miss Chen, could you tell me _? It is short for the Silk Road Ec
32、onomic Belt and 21st Century Maritime Silk Road. A.what the Belt and Road meant B.what does the Belt and Road mean C.what the Belt and Road means D.what is the Belt and Road meant 18.David asked _ in China. Of course not.Chinese usually shake hands with a lady as a greeting. A.why he can greet a lad
33、y by kissing her B.why he could greet a lady by kissing her C.whether he can greet a lady by kissing her D.whether he could greet a lady by kissing her 19.Show me the map, please.I wonder _. Look, its here, in the east of China. A.where is the island B.where the islandis C.whatis the islandlike D.wh
34、enthe islandis 20.Could you please tell me _? About twenty minutes ago. A.whendidyou see this kid B.where didyou see this kid C.when you saw this kid D.where you saw this kid 21.To make your DIY work perfect, youd better not start _ you get all the tools ready. A.when B.while C.before D.after 22.The
35、y spoke _ quietly _ I could hardly hear them. A.such;that B.so;that C.neither;nor D.both;and 23.I am really proud of my group _ were always discussing and sharing study secrets together.How important the group work is! A.because B.though C.unless D.while 24.Its already tens of years _ the worlds pop
36、ulation reached five billion. A.before B.after C.since D.unless 25._Jack was a little disappointed, he still went on with his work. A.Although B.Because C.Since D.If 26.Shirley is the girl _ taught me how to use WeChat（微信）. A.whom B.which C.who D.when 27.It is the most beautiful city _ I have ever v
37、isited. A.where B.that C.when D.which 28.Which song do you like better, Lucy? I prefer the song Little Apple_ attract many people A.which B.who C.whom D.where 29.This is the school _ I studied three years ago. A.where B.when C.that D.which 30.Could you tell me who to ask for advice about my trip nex
38、t week? Can you see the girl _ is in red? She knows whether the place is worth _. A.who;visiting B.whom;enjoying C.that;playing D.which;seeing One boy is a boy, two boys half a boy, three boys no boy. 一个和尚挑水喝，两个和尚抬水喝，三个和尚没水喝。 One cannot put back the clock. 时钟不能倒转。 One eyewitness is better than ten hearsays. 百闻不如一见。 One false move may lose the game. 一着不慎，满盘皆输。 One good turn deserves another. 行善积德。
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