状语从句按其意义和作用的划分

1、状语从句按其意义和作用可分为a）时间状语从句b）地点状语从句c）原因状语从句d）目的状语从句e）结果状语从句f）条件状语从句g）方式状语从句h）比较状语从句i）让步状语从句2. 时间状语从句whe n, no sc等弓导。如ha n弓丨导时间状语从句的从属连词有：whe n, while, as, whe never, before, after, sin ce, till, un til, as soon as, on ce, hardlyWhen he was still a young man, he was forced to leave his homeland for politi

2、cal reas ons.a）whe n, as, whilei. when即可引导持续性动作，又可引导短暂性动作。它可以表示主句的动作和 从句的动作同时发生，或从句的动作发生在主句动作之前。如：Whe n I was a boy, I used to go to the seashore on Sun days.（同时）When the less on was over, we bega n our writ ing.（从句动作在前）ii. as引导持续性动作，侧重主句和从句的动作同时发生。He hurried home, look ing behi nd as he went.I saw

3、your sister as she was gett ing on the bus yesterday.He sang as he walked.iii. While :指的是 在某一时间里”，在期间”，从句里的动作必须是持续性的，它也强调主句和从句动作的同时发生，往往侧重主句和从句动作的对比。如:While he was in London, he studied music.While we were watch ing TV, he was writi ng a compositi on.while也可做并列连词，表示对照的含义，意思为 而”。女口：He is tall while h

4、is brother is short.当when, as, while表示 在一段时间里”,主从句的动作同时发生时，可以换用。 女口： While （When 或 As） we were discussing, Mr. Smith came in.b）如果when和before引导的从句位于主句之后，有时不能译成当时候”和在之前”，而要译成就”、才”、这时”等。如：The struggle lasted four years before the North won in the end.He almost kno cked me dow n before he saw me.She had

5、 not bee n married many weeks whe n the man saw her and was struck by her beauty.I was walk ing in the street whe n I saw him.c) by the time, each time, every time, immediately, the mome nt, the in sta nt, the mi nute, soon after, shortly after 都可以作为连词，引导时间状语。如：By the time he was fourtee n, he had t

6、aught himself adva need mathematics. Each time he came, he would call on me.You must show him in immediately he comes.I recog ni zed him the mome nt I saw him.d) by the time 的用法i. by the time+现在时，主句用将来完成时.例如：By the time he arrives, we will already have left California.ii. by the time+ 一般过去时，主句用过去完成时

7、.例如：By the time he arrived, we had already left Califor nia.e) till 和 untili. 如果主句谓语动词是持续动词，通常用肯定式的主句，表示 直到为止” 如:I worked till (un til) he came back.ii. 如果主句谓语动词是瞬间动词，则用否定式的主句表示直到才”女口：I didn t go to bed until (till) he came back.iii. 放在句首表示强调时一般用un til。如：Un til he retur ns, nothing can be done.Not u

8、n til his mother called did he get up.(不倒装为 He didn t get up until his mother called.)It was not un til his mother called that he got up.(not until 的强调结构为 it is/was not untilthat )f) before的句型：i. It won t be long before sb. does sth不用多久某人就会 ii. It will be long before sb. does要过很久某人才会iii. It was long

9、 before sb. did sth.过很久某人才做iv. It will be + 一段时间+ before sb. does 某人要过多长时间才做v. It was + 一段时间+ before sb. did sth. 某人过了多长时间才做g) 用no sooner than和hardlywhen引导的从句表示 刚就”，主句中的动词一般用过去完成时，从句用过去时若把no soo ner, hardly提到句首，主句倒装例如：He had no sooner got to the lab tha n he set out to do the experime nt.(该句倒装为： No

10、sooner had he got to the lab tha n he set out to do the experime nt.)h）时间状语从句中谓语动词不能用任何一种将来时，只能用现在时和过去时表示将来时。3. 地点状语从句：通常由连词 where和wherever等引导。如：Go back where you came from.Wherever you go, you must write to your pare nts.Where there is a will, there is a way.Where there is too much, the poison and

11、waste may do great harm to the things around us.4. 原因状语从句：通常由连词： because, as, sin ce, now that 弓丨导。a）区别是:because :表示 因为”直接而明确的原因和理由，语气最强，why提问的句子， 一般都用because回答。He didn t come because he was ill.since ： 表示 既然”语气比 because 弱。Since you are here, you must do it.as :表示因为”语气比because轻，引导从句可放主句前也可放主句后。You n

12、eedn t go with me, as you are busy.As I was afraid, I hid myself.now that意思与since相似，表示既然”Now that you are in High School, you will probably spe nd more in read ing.Now that all the guests have arrived, let s have our dinner.b）注意：i. 在强调句中强调原因状语从句，只能用because引导，不可用as或since，如:It was because he was ill t

13、hat he didn t go with us.ii. because可以引导表语从句，而as, since不可以，这时主语一般都是it, this, thatIt s because he is too lazy.for:也表示 因为”但是并连词，它连接的不是状语从句，语气比较强。 For引导 从句不说明主句发生的直接原因，只是提供一些补充说明，且不位于句首.It must be morni ng,for the birds are sin gi ng.seeing that （既然）和 in that （因为）Seeing that the weather is bad, we ll s

14、tay at home.I like the city, but I like the country better in that I have more friends in the coun try.5. 目的状语从句：通常由 that, so that, in order that, so that, lest, in case (以防、免得)等引导: He got up early in order that he could catch the early bus.She married him so that she might tend and comfort him.I ex

15、pla ined aga in and aga in in case he should misun dersta nd me.目的状语从句中谓语动词常含有 may (might), can (could) should, will 等情态动词。lest (以免，免得),for fear thatI hid the book lest (=for fear that) he should see it.6. 结果状语从句：由 that, so that, so that, such 引h导:It was very cold, so that the river froze.The book i

16、s so written that it gives a quite wrong idea of the facts.There were so many people (=such a lot of people) in the room that we could not get in.He made such an excelle nt speech that every one admired him.7. 条件状语从句：由 if, uni ess, as long as (=so long as)( 只要),in case (that)(女口果，万一)等引导: If plastics

17、 and rubber are burned, they give off poisonous gases.Un less you work hard, you will fail,You can go out, as long as (so long as ) you promise to be back before eleve n.In case I forget, please rem ind me about that.注意：条件状语从句中的谓语动词的时态不可用将来时，只能用现在时态或过去时态表示将来时。8. 方式状语从句：由连词：as, as if, as though 弓丨导：T

18、he teacher told the stude nts to do as he did.Leave it as it is.He heard a no ise, as if some one was breath ing.I saw the man looking about him as if he wished to impress upon his mind everyth ing.as if和as though意义和用法大致一样，引导的从句多用虚拟语气，但也可用陈 述语气。He treats me as if I were his own son.He walked as if h

19、e were drunk.9比较状语从句：由连词 asas, not so(as) as, tha等弓丨导：I hope it was as good as the one you lent me.Actually the ocea n floor are almost as irregular as the exposed land area.No one can be more fit for his office than he is.He can t run so fast as she.注意：“the比较级(接从句)，the+比较级(接主句)，这一句型也归在比较状语从 句内。如：The more you study, the more you know.The harder we work, the happier we feel.10.让步状语从