英语中的状语从句共有九类，这些状语从句各有其引导词，有的引导词又可以引导不同的类型的状语从句，其详细用法如下。

　　1. 时间状语从句：由when, whenever, as, while, after, as soon as , till (until), since, once(一旦)等指导。

　　2. 地点状语从句：由where, wherever引导。

　　3. 原因状语从句：由because, as, since, now that等引导。

　　4. 目的状语从句：由that, so that, in order that, for fear that(唯恐，以免), lest, in case(以防，免得)等引导。

　　5. 结果状语从句：由that, so that, so...that, such… that等引导。

　　6. 条件状语从句：由if unless, as long as, in case (that) (如果，万一)等引导。

　　7. 方式状语从句：由as (如，像)和as if／though引导。

　　8. 比较状语从句：由as…as，not so (as)…as, than等引导。

　　9. 让步状语从句：由though, although, as (虽然，尽管), even if／though, whoever, whatever, whichever, whenever, wherever, however, no matter who／ what／which／when／where／how, whether等引导。

　　直击高考

　　1. The WTO cannot live up to its name ____ it does not include a country that is home to one fifth of mankind. (NMET 2000)

　　A. as long as B. while C. if D. even though

　　2. The men will have to wait all day ____ the doctor works faster. (NMET 2001春)

　　A. if B. unless C. whether D. that

　　3. —Did you remember to give Mary the money you owed her?

　　—Yes, I gave it to her_____ I saw her. (NMET2001春)

　　A. while B. the moment C. suddenly D. once

　　4. Don’t be afraid of asking for help it is needed. (NMET2003)

　　A. unless B. since C. althoughD. when

　　5. —Was his father very strict with him when he was at school?

　　—Yes. He had never praised him____ he became one of the top students in his grade. (2003北京)

　　A. after B unless C. until D. when

　　6. We were swimming in the lake _______ suddenly the storm started.

　　A. whenB. while C. untilD. before

　　7. _______ I can see, there is only one possible way to keep away from the danger. (2004北京春)

　　A. As long asB. As far as C. Just as D. Even if

　　8. Someone called me up in the middle of the night, but they hung up ___ I could answer the phone. (NMET2000)

　　A. as B. since C. until D. before

　　答案与分析

　　1. C 此题考查连词。A意为“只要”，B为“当……时”或“然而”，C为“如果”，D为“即使”。本句译为：如果WTO不接收一个拥有世界人口五分之一的国家，它就愧对它的名字。

　　2. B此题是连词unless引起一个条件状语从句的用法。根据题意，“如果医生不快点工作的话，人们就会等上一整天”，只有B合意。

　　3. B此题考查the moment 作连词的用法。它表示“—……就……”，相当于 “as soon as…”的含义。根据句意，只能选B, While所连的句子中的谓语动词必须是延续性的。

　　4. D本题考查从属连词的用法。unless相当于if …not,引导条件状语从句。since引导时间状语从句时，表示“自从……以来”；引导原因状语从句时，表示“因为，既然”。although引导让步状语从句，表示“虽然、尽管”。A、B、C各项填入空白均与语境不符。此空应填when，表示条件，相当于 if, 意为 “如果，假如”。故答案为D。

　　5. C我们极易错选B。unless表达的是一种条件，意思是“除非……”，如I will never go to his birthday party unless he invites me. 在本句中he invites me是条件，go to his birthday party是结果。解题时我们要注意空前的had never praised用的是过去完成时，它表达的是发生在became前的动作，因此这是一组先后的动作，而不是条件。never…until意思是“直到……才”，相当于not … until。本句的意思是“直到他成为年级最好的学生之一，他父亲才表扬他。”故答案是C。

　　6. A be about to do…when为固定搭配，意思是“正要做某事，就在这时……”。

　　7. B As far as I can see为状语从句，意思是“根据我能看到的”。A有一定干扰性，as long as意思是“如果”，不合题意。

　　8. D before在这里与情态动词连用，表达“没有来得及”的意思。

　　专项训练

　　1. He’s got himself into a dangerous situation____ he is likely to lost control over the plane.

　　A. where B. which C. while D. why

　　2. Information has been put forward____ more middle school graduates will be admitted into universities

　　A. while B. that C. when D. as

　　3. ____ air is to man, so is water to fish.

　　A. Since B. Just C. Like D. As

　　4. There is plenty of rain in the south_____ there is little in the north.

　　A. while B. as C. when D. so

　　5. —I don’t like chicken ____ fish.

　　—I don’t like chicken, ____ I like fish very much.

　　A. and; and B. and; but C. or; but D. or ; and

　　6. _____the days went on, the situation there got worse.

　　A. With B. Since C. While D. As

　　7. ____ everybody is here, here, let’s set out right away.

　　A. Now that B. Because. C. For D. After

　　8. _____I know, they will go to Beijing to watch the Olympic Games in 2008.

　　A. Since B. So far as C. In case D. As if

　　9. You should put the dictionary____ you can find it easily.

　　A. where B. the place C. the place on which D. what

　　10. She said to me, “I’ll tell you the result of test ____ I know it.”

　　A. because B. the moment C. after D. though

　　11. Grandpa used to tell us something about the “Cultural Revolution”____ he had time to spare.

　　A. as soon as B. as C. so that D. whenever

　　12. Li Fang is very busy, ____ she’s always helping others with their lessons.

　　A. but B. although C. so D. for

　　13. Getting a right job can be difficult ____ the students ____prepared to deal with the job interview.

　　A. if; won’t B. unless; will C. unless; are D. if; are

　　14. It’s really very dangerous. One more step, ____ the baby will fall into the well.

　　A. or B. so C. but D. and

　　15. She is American, _____she knows little about American history.

　　A. so B. yet C. and D. therefore

　　16. Information technology is taught in most schools, ____ we have entered the information society.

　　A. so B. while C. still D. for

　　17. It was quite a long time ____ I made it out what had happened.

　　A. after B. before C. when D. since

　　18. ____ the text a second time, the meaning will become clearer to you.

　　A. Read B. Reading C. If reading D. When you read

　　19. ____, so he didn’t come to school last week.

　　A. Though he was ill B. Being ill C. Having been ill D. He was ill

　　20. ____ you go, you should bear the motherland in mind.

　　A. Where B. Whenever C. However D. Wherever

　　答案与分析

　　1. A 题中a dangerous situation是表示地点概念的名词，故其后要用关系副词where引导定语从句。

　　2. B 题意：更多的中学生毕业后将进入大学的信息已被提出来了。由于主句用了被动结构，抽象名词information本提前；主句后应是说明information的具体内容的同位语从句，从句中无须添加任何成分，故用that引导。

　　3. D 由as, just as引导的方式状语从句，有时也可放在句首，主句前常加so与之呼应，以加强语气，而且用倒装语序。本句可译为：空气对于人，犹如水对于鱼。

　　4. A while意为“而，却”，表示两者的对比，这时它引导的是并列分句。

　　5. C 在否定句中，并列成分的连接通常用or , 构成完全否定；答语中前后两分句是一种转折关系，故用but连接。

　　6. D as the days went on=with the days going on 意为“随着日子一天天过去。”

　　7. A now (that) 在此表示原因，意为“既然，由于”；because表示对方不知道的原因；for 表示原因时，是并列连词，应放于句中。

　　8. B so far as I know意为“据我所知”。

　　9. A 此处where引导地点状语从句。

　　10. B the moment意为“一……就”，相当于as soon as。类似用法的连词还有: the minute/ instant; instantly/ immediately/ directly等。

　　11. D 本题考查时间状语从句，表示“无论何时”，因此用whenever (=no matter when)来引导从句。

　　12. A 根据题意应用连词but表示转折。

　　13. C unless表示“除非，如果不”；be prepared to do 意为“准备好做某事”。

　　14. D 本句为祈使句+and/ or并列分句的句型。One more step= Walk one more step。

　　15. B yet用作并列连词，可以表示转折或对照，意为“但是，然而”。与but相比语气稍弱。

　　16. D for 用作并列连词，连接两个并列分句，后一分句起对前一分句进行一步解释或推断的作用。

　　17. B 在 “It+ be+时间名词+before/ since-从句”句型中，连词before 与since极易混淆。用before引导时，句意是“过了多久才……”，主句中的be动词为过去时或将来时态；用since引导时，其句意是“自从……以来已经多久了”，主句中的be动词多为现在时(或现在完成时)或一般过去时(此时since-从句要用过去完成时。

　　18. D 选A项。错误在于分句间缺少并列连词；选B项，错误在于主句的主语并非reading的逻辑主语。

　　19. D so连接表示因果关系的并列句。

　　20. D 题意为“无论走到哪里，都要牢记祖国母亲”。wherever引导让步从句。