状语从句-正式

1、状语从句,状语从句在句中作状语，修饰主句中的动词、形容词或副词等。状语从句放在主句之前时，常用逗号分开；放在主句之后时，一般不用逗号。状语从句按其意义和作用可分为时间、条件、原因、让步、目的、结果、方式、比较、地点等9种。,状语从句的分类,1、时间状语从句：,注意： （1）when, as, while 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：,When I was a boy, I used to go to the seashore on Sundays.（同时） When the lesson was

2、over, we began our writing. （从句动作在前）,as引导持续性动作，侧重主句和从句的动作同时发生。 I saw your sister as she was getting on the bus yesterday. He sang as he walked.,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 we were watching TV, he was writing a composition.,while也可做并列连词，表示对照的意思。如：,

3、He is tall while his 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。如：,While (When或As) we were discussing, Mr. Smith came in.,(2) by the time, each time, every time, immediately, the moment, the instant, the minute, soon after, shortly after都可以作为连词，引导时间状语。,by the time 1)到时候为止 通常引导一个时间

4、状语从句，表示“到的时候为止”主句则表示在此时间之前某个事件已完成。值得注意的是，当从句用过去时时，主句通常用过去完成时。 例如： By the time l got to the station，the train had already gone。 By the time he was fourteen, he had taught himself advanced mathematics. By the time you get to get to Greenwich you will have seen the most historic parts of London.,soon a

5、fter 不久以后 Paula became pregnant soon after they were married. Shortly after那不久之后 .那以后不久 I began to clean the classroom shortly after I got to school,Each time he came, he would call on me. You must show him in immediately he comes. I recognized him the moment I saw him.,(3) till和until 如果主句谓语动词是持续动词，

6、通常用肯定式的主句，表示“直到为止”。如： I worked till (until) he came back., 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”。如：,I didnt go to bed until (till) he came back.,放在句首表示强调时一般用 until。如：,Until he returns, nothing can be done.,2、地点状语从句：,通常由连词where,wherever和everywhere 引导。如：,Go back where you came from. Wherever you go, you mus

7、t write to your parents. Where there is a will, there is a way. She follows me everywhere I go.,3、原因状语从句：,通常由连词：because, as, since, now that引导。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 didnt come because he was ill.,since：表示“既然”，语气比because弱。,Since you are here, you must do i

8、t.,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 neednt 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 spend more in reading. Now that all the guests have arrived, lets have our dinner.,注意： 在强调句中强调原因状语从句， 只能用becau

9、se引导，不可用as或 since，如： It was because he was ill that he didnt go with us., because可以引导表语从句,而 as, since不可以，这时状语一 般都是it, this, that,Its because he is too lazy., for也表示“因为”，但是并列 连词，它连接的不是状语从 句，语气比较强。,It must be morning,for the birds are singing.,4、目的状语从句：,通常由that, so that, in order that, lest, in case（以

10、防、免得）等引导：,He got up early in order that he could catch the early bus. She studied hard so that she could pass the final-exam. I explained again and again in case he misunderstand me.,lest (以免，免得), for fear that I hid the book lest (=for fear that) he see it.,目的状语从句中谓语动词常含有may (might), can (could) sh

11、ould, will等情 态动词。,5、结果状语从句：,由that, so that, sothat, suchthat引导： It was very cold, so that the river froze. There were so many people (=such a lot of people) in the room that we could not get in. He made such an excellent speech that every one admired him.,6、条件状语从句:,由 if, unless, as long as (=so long

12、 as) (只要), in case (that) (如果，万一)等引导：,If plastics and rubber are burned, they give off dangerous gas.,Unless you work hard, you will fail, You can go out, as long as (so long as ) you promise to be back before eleven.,In case I forget, please remind 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，只能用现在时态表示将

13、来时。,7、方式状语从句：,由连词：as, as if, as though引导： The teacher told the students to do as he did. Leave it as it is. He heard a noise, as if someone was breathing.,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He treats me as if I were his own son. Smith talked as he had done all the work himself,but in fact Tom and I

14、 did most of it.,8、比较状语从句：,由连词asas, not so(as) as, than等引导：,I hope it was as good as the one you lent me.,No one can be more fit for his office than he is.,He cant 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 hap

15、pier we feel.,让步状语从句一般由如下的词或词组引导： 1）though, although2）even though, even if3）whatever, whenever, however(+ adj.), whetheror not, no matter whether or not.,9、让步状语从句：,whatever whoever whichever whenever wherever however,wh - ever,no matter who no matter what no matter which no matter when no matter whe

16、re no matter how,no matter wh-,Though he is old, yet he is active. Although most of the people agreed, some were not willing to accept. Young as the child is ,he knows something about electricity. We wouldnt lose heart even if we should fail ten times.,Whenever (=no matter when) you call on me, you

17、are always welcome. Wherever (no matter where) you work, you can always find time to study. Take the one you like best, whichever (no matter which) it is.,No matter what I say or how I say it, he always thinks Im wrong.,Whether he comes or not, well discuss the problem this afternoon.,注意： （1）让步状语从句在

18、句中的位置可放前也可放后，有时还可以插在主句中间，前置时，强调主句内容，后置时强调从句内容。,（2）though与although同义，用法基本一样，前者通俗，口语化；后者较正式，多放于句首，不能与but连用，但可以与yet, still等连用，用来加强语气。Though ( Although ) he was tired, yet (still) he went on working.,（3）as引导让步状语从句时从句部分 语序要部分倒装。如：,Young as he is, he can read and write in several foreign language. （表语提前）,Child as he was, he had to support the family. （表语名词提前并常省去冠词） Surrounded as we were by th