1、状语从句（一）状语从句概述定义状语从句用作状语，是起副词作用的句子。位置状语从句可以放在主句之前，也可以放在主句之后，时间、条件、原因和让步状语从句放在句首时需要用逗号和主句隔开。分类根据其作用可以分为时间、地点、原因、条件、目的、让步、方式和比较等状语从句。作用它可以修饰谓语、非谓语动词、定语、状语和整个句子。（二）状语从句详解1. 时间状语从句引导词用法示例when意为“当的时候”。When引导从句的谓语动词可以是延续性动词，也可以是瞬间动词。并且when有时表示“就在那时”A liar is not believed when he speaks the truth.说谎者讲真话时也没有
2、人相信。When he arrives, Ill call you.When you laugh and smile, your body relaxes. while意为“在的时候，在的同时”。While引导从句的谓语动词必须是延续性的，发生时间较长，并强调主句和从句的动作同时发生（或者相对应）。While有时还可以表示对比。While I was standing at the window, I saw several boys running along the street. While John was watching TV, his wife was cooking. as意为
3、“一边一边”。As引导的动作是延续性的，发生时间较短，一般用于主句和从句动作同时发生；as也可以强调一前一后。The writer was angry as he was travelling on a train to London because someone had invaded his “space”.He smiled as he stood up. after意为“在之后”。表示主句动作发生在从句动作之后。主句与从句的动作时间关系与before引导的从句相反。With many hungry visitors waiting, dont stay too long at you
4、r table after you have finished.If an early exit is necessary, you can leave after a scene is over. before意为“在之前”。引导的从句不用否定形式的谓语，并且当before引导的从句位于主句之后，有时译成“就，才”。当主句用将来时，从句总是用现在时；如果before引导的从句谓语用的是过去时，则主句动词多用过去完成时，这样以便体现动作的先后。You cant watch TV before you finish your homework.Before it ended, the theat
5、re was almost empty. My father had left for Canada just before the letter arrived.till意为“直到”。一般情况下可以和until互换。如果主句中的谓语动词是瞬时动词时，必须用否定形式；如果主句中的谓语动词是延续性动词时，用肯定和否定形式都可以，但表达的意思不同。She didnt even know that it was an earthquake till she saw a shaking ( moving from side to side) light.The fireman worked very
6、hard till the fire was out.until意为“直到”。在强调句型中多用until。如果主句中的谓语动词是瞬时动词时，必须用否定形式；如果主句中的谓语动词是延续性动词时，用肯定和否定形式都可以，但表达的意思不同。Im waiting for my sister. I wont go to see my uncle until she comes.Wait until I finish what I am doing.since意为“自从，从以来”。引导从句的谓语动词可以是延续性的动词，也可以是瞬时动词。一般情况下，从句谓语动词用一般过去时，而主句的谓语动词用现在完成时。但
7、在It is +时间+since从句的句型中，主句多用一般现在时。I have been studying hard since I entered the high school.It is four years since my sister lived in Beijing.It is five years months since our boss was not in Beijing.as soon as意为“一就”。引导时间状语从句时，如果主句用了将来时，从句一般使用现在时。Tom will call me as soon as he gets home.I will call y
8、ou as soon as I arrive.2.地点状语从句引导词用法示例where意为“哪里”。“where引导的地点状语从句，（there+）主句”“哪里哪里就”。主句在从句后面时，there可用可不用；主句在从句的前面时，一般都不用there.Where there is a will, there is a way. They were good persons. Where they went, there they were warmly welcomed.You should have put the book where you found it. wherever意为“无论
9、何地”。anywhere/wherever引导地点状语从句+主句。anywhere本身是个副词，但是常可以引导从句，相当于连词，意思相当于wherever, anywhere引导的从句可位于主句之前，也可以位于主句之后。而wherever本身就是个连词，表示“在何处，无论何处”。Wherever the sea is, you will find seaman.Ill go anywhere you go.3.条件状语从句引导词用法示例if连词，意为“假如，如果”。当主句是将来时的时候，从句要用一般现在时。Dont talk loudly at the meeting. If you do,
10、you will have to leave.Well go for a picnic if it doesnt rain this weekend.unless连词，意为“除非（=if not）。当主句是将来时的时候，从句要用一般现在时。Dont discuss the problems with your partner unless you are asked to do so. I wont go there unless you come with me.4.原因状语从句引导词用法示例as意为“因为”。引导原因状语从句时表示附带。说明“双方已知的原因”，语气比since弱，较为正式，
11、位置较为灵活（常放于主句之前）。As the weather is cold, I stay at home.As it is raining, youd better take a taxi.As you are tired, youd better rest. since意为“因为”。引导的原因状语从句一般放于主句之前表示已知的、显然的理由（通常被翻译成“既然”），较为正式，语气比because弱。Since the earth looks like a ball, the sun can shine on only half of it at a time. Since the race
12、 is in April, I had to run throughout the winter, and in Boston, winters are cold.Since everybody is here. Lets begin our meeting.because意为“因为”。引导的原因状语从句一般放于主句之后，表述直接原因，语气较强，最适合why引导的疑问句。Because引导的原因状语从句有时可以与because of短语互换。The woman prefers winter because she can skate.Id like to collect stamps beca
13、use they are interesting.Im very tired these days because of studying physics.He cant come because he is ill. = He cant come because of his illness.for意为“因为”。引导的原因状语从句并不说明主句行为发生的直接原因，只提供一些辅助性的补充说明，for引导的原因状语从句只能放于主句之后，并且必须用逗号将其与主句隔开。He must be ill, for he is absent today.He could not have seen me, f
14、or I was not there. 5.目的状语从句引导词用法示例so that意为“以至，以便”。目的状语的谓语常含有may, might, can, could, should, would等情态动词。Try to speak loud enough so that people can hear you clearly.Mr. Green speaks very loudly so that all the people can hear him clearly. in order that意为“为了”，相当于so that. in order to后面可以跟动词原形构成目的状语，不
15、是目的状语从句。We shall let you know the details soon in order that you can/may make a arrangements.6.结果状语从句引导词用法示例sothat意为“如此以至于”。so+ adj./adv.原级+that, so是副词，只能修饰形容词和副词。so还可与表示数量的形容词many, few, much, little(这四个形容词表示多或少时)连用,形成固定搭配。so+ many 或few+复数可数名词+that; so+ much或little+不可数名词+that.This year it has rained
16、 so heavily in South China that lots of problems are caused.The ice on the lake was so thin that people couldnt skate on it. Too often, we spend so much time thinking about the future that we fail to enjoy the present.There are so few notebooks that I cant give you any.such.that意为“如此以至于”。有三种结构：such+
17、a(an)+adj.+单数不可数名词+that; such(+adj.)+不可数名词+that; such( + adj.) +复数可数名词+that, such是形容词，修饰名词或名词词组。有时可与sothat句型转换。Its such a wonderful song that we all like it.Simon is such dishonest person that no one believes him.The boy is so young that he cant go to school.= He is such a young boy that he cant go
18、to school.7.让步状语从句引导词用法示例though意为“虽然”。不能和but连用。但是可以同yet(still)连用，构成thoughyet(still). though较普遍，常用于非正式的口语和书面语中。even能和though组合表示强调，在这里even though=even if(no matter if; though即使也)。though可以独立用作副词，常放在句末，意为all the same(还是；仍然)或however(可是；然而)。So it has lived up to now though it isnt strong at all.Though the
19、y are twin brothers, they dont look like each other.Even if/ Even though we could afford it, we would afford it, we wouldnt go abroad for our vacation. although意为“虽然”。不能和but连用。但是可以同yet(still)连用，构成althoughyet(still). although 较为正式，语气比though重，常用以强调让步概念。 even不能和although组合。Although he died several years
20、 ago, I can still remember the days we spent together and what he has taught me about love.Although we had little food with us, we decided to spend the night in the car.8. 比较状语从句引导词用法示例asas.意为“和一样”。表示同级的比较。使用时要注意第一个as为副词，第二个as为连词。其基本结构为：as+adj./adv.原级+as。若有修饰成分，如twice, three times, half, a quarter等，
21、则须置于第一个as之前。She is very good at painting. She can paint as well as here teacher.I ran out as quickly as possible. not as / soas意为“和不一样，不如”。也表示同级比较。She is not so (as ) outgoing as her sister. This dictionary is not as/so useful as you think. 9.方式状语从句引导词用法示例as/(just)as.so意为“犹如，就像”。引导的方式状语从句通常位于主句后，但在(
22、just)as.so结构中位于句首，这时as从句带有比喻的含义，意为“正如，就像”，多用于正式文体。When in Rome, do as the Romans do.As water is to fish, so air is to man. as if/ as though意为“就像，好像”。两者的意义和用法相同，引出的状语从句谓语多用虚拟语气，表示与事实相反，有时也用陈述语气，表示所说情况是事实或实现的可能性较大。常译作“仿佛似的，好像似的”。If would never forget here smile, or the way her eyes shone as if we were
23、 the same age. It looks as if the weather may pick up very soon. 练习一一. 单项填空1. _ hes old, he can still carry this heavy bag. A. Though B. Since C. For D. So2. -Do you know if he _ to play basketball with us? -I think he will come if he _ free tomorrow. A. comes; is B. comes; will be C. will come; is
24、D. will come; will be3. In the zoo if a child _ into the water and cant swim, the dolphins may come up _ him. A. will fall; to help B. falls; to help C. will fall; help D. falls; helping4. I dont remember _ he worked in that city when he was young. A. what B. which C. where D. who5. We will stay at
25、home if my aunt _ to visit us tomorrow. A. comes B. come C. will come D. is coming6. The police asked the children _ cross the street _ the traffic lights turned green. A. not; before B. dont; when C. not to; until D. not; after7. I was late for class yesterday _ there was something wrong with my bi
26、ke. A. when B. that C. until D. because8. Ill go swimming with you if I _ free tomorrow. A. will be B. shall be C. am D. was9. In the exam, the _ you are, _ the _ mistakes you will make. A. careful; little B. more careful; fewest C. more careful; fewer D. more careful; less10. You should finish your
27、 lessons _ you go out to play. A. before B. after C. when D. while11. I hurried _ I wouldnt be late for class. A. since B. so that C. as if D. unless12. When you read the book, youd better make a mark _ you have any questions. A. which B. that C. where D. though13. The teacher raised his voice _ all
28、 the students could hear him. A. for B. so that C. because D. in order14. He took off his coat _ he felt hot. A. because B. as C. if D. since15. It is _ that wed like to go out for a walk. A. a lovely day B. too lovely a day C. so lovely a day D. such lovely a day16. Mary had _ much work to do that
29、she stayed at her office all day. A. such B. so C. too D. very17. _ I felt very tired, I tried to finish the work. A. Although B. Because C. As D. As if18. _ the day went on, the weather got worse. A. With B. Since C. While D. As19. _ well you can drive, you must drive carefully. A. So long as B. In order that C. No matter how D. The moment20. Write to me as soon as you _ to Beijing. A. will get B. get C. getting D. got答案1.A 2.C 3.B 4.C 5.A 6.C 7.D 8.C 9.C 10.A 11.B 12.C 13.B 14.A 15.C 16.B 17.A 18.D 19.C 20.B
