状语从句(知识讲解)

1、.状语从句概念引入：状语从句是句法考试的重要内容。必须掌握以下语法知识：状语从句的引导词与介词的用法比较；状语从句中意义近似的连接词的用法比较；状语从句与定语从句引导词的用法比较等等。 状语从句的考察重点是意义近似的连接词的用法。考察状语从句的试题选项不仅有连词，有时还从定语从句和名词性从句的角度进展干扰，出现代词和介词。Leave your key with a neighbor in case you lock yourself out one day. 目的状语从句：“给邻居留一把钥匙的目的是“万一某一天把自己锁在门外时可以用到，从句表示主句动作的目的。The field researc

2、h will take Joan and Paul about five months; it will be a long time before we meet them again.时间状语从句：“野外研究要花掉John和Paul大约五个月，我们再次见到他们将是很长时间。before从句表示再次见到他们的时间。 I wont call you, unless something unexpected happens. 条件状语从句：“给你打 的条件是“意外的事情发生。语法讲解时间状语从句1when，while，as都可译为“当的时候，但侧重点有所不同。当主句是瞬间动作而从句是延续动作时，

3、三者都可以用。as强调主、从句动作同时或几乎同时发生。while从句的谓语必须是延续的，不能是非延续性动词。She sang as we walked. I listened carefully while she was singing，and we felt happy when we got home.我们一边走她一边唱，她唱的时候我认真听。到家的时候我们感觉很快乐。2until 和not.untiluntil要与延续性动词连用；not.until 要与非延续性动词连用。He didnt go to bed until his father came back.3特殊的时间状语从句的引导

4、词：1the moment，the minute，the instant，the second；no sooner.than.；hardly/scarcely.when.等以及表示瞬间的directly，immediately，表示“一就，相当于as soon as。no sooner.than.，hardly/scarcely.when.构造中no sooner和hardly/scarcely引导的句子中谓语动词通常用过去完成时，而than和when引导的句子中谓语动词通常要用一般过去时，此外，no sooner和hardly/scarcely位于句首时，句子应用部分倒装语序。Tell hi

5、m the news the minute you meet Tom.Hardly had I got home when it began to rain.2next time，the first time，last time，every time，the spring summer，autumn，winter等，这类短语名词直接用作连词引导时间状语从句。Every time I see him he wears a pleasant smile.4by the time 也可以引导时间状语从句，意为“到时为止，主句一般用完成时态。By the time he was fourteen，Ei

6、nstein had learned advanced mathematics all by himself.从句为一般过去时，主句要用过去完成时5几组固定形式1It will be一段时间before. 多久之后才2It is一段时间since. 自从以来已有多长时间了。3 be about to do.when.；be doing.when.；on the point of doing.when.It will be two days before he returns.It is three years since I came here. I was doing my homework

7、 when my cousin came.原因状语从句1. because引导的原因状语从句一般放于主句之后， because表示直接原因， 语气最强， 最合适答复 why引导的疑问句。I do it because I like it. 我做这件事是因为我喜欢。注意：“not . because构造中的not否认的是because引导的整个从句。The country is not strong because it is large. 国强不在大。2. since引导的原因状语从句一般放于主句之前表示的、显然的理由通常被翻译成“既然， 较为正式， 语气比because弱。Since you

8、 are free today, you had better help me with my mathematics. 既然今天你休息， 你最好帮我补习数学。注意：seeing that，now that，considering that，in that这几个词汇与since引导的原因状语从句意思相近， 都表示“既然。Seeing that he refused to help us, theres no reason that we should now help him. 他既然曾经回绝帮助我们，我们如今没有理由要来帮助他。In that he is ill, he feels unab

9、le to do it. 因为有病，他觉得做不了那件事。3. as引导原因状语从句时表示附带说明的“双方的原因，语气比since弱，较为正式，位置较为灵敏常放于主句之前。As it is raining, youd better take a taxi. 既然在下雨，你最好乘出租汽车。4. for引导的原因并列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引导的句子只能放于主句之后并且必须用逗号将其与主句隔开。He could not have seen me, for I was not there. 他不可能见过我，因为我不在那里。条件状语从句1. if 表示正面的

10、条件，意为“假如；unless =if not 表示负面的条件，意为“除非，假如不。If you ask him, he will help you. 假如你恳求他，他会帮助你。He is sure to come unless he has some urgent business. 他一定会来，除非他有急事。2. in case，on condition that，providing，provided that，supposing，suppose that等词汇意思相近， 指“假设， 假使， 在条件下比if更为书面化。In case he comes, let me know. 假如他来的

11、话，告诉我一声。I will go, providing/provided that my expenses are paid. 只要我的费用有人付，我就去。 Suppose/Supposing that he does not come, what shall we do? 他要是不来，我们该怎么办？3. as long as =so long as 表示充分必要条件，引导语气强烈的条件状语从句时，意为“只要。I will cooperate as long as I am notified on time. 只要及时告诉我，我就会合作。You may use the book so lon

12、g as you will return it on time. 只要你准时还，你就可以借这本书。让步状语从句引导让步状语从句的连词有：though，although，even if/ though，however，no matter how，no matter what，no matter who等。1though，although引导让步状语从句时都不能和but连用，但可以同yet still 连用。Although he is rich，yet he is not happy.2as引导的让步从句时，从句要采用倒装语序。Child as /though he was，he knew wh

13、at was the right thing to do. Try hard as he will，he never seems to do the work well.Young as/though he is, he is expert in this field.3whether.or not意为“无论是否。Whether you believe it or not，it is true.4however形容词/副词 no matter how形容词/ 副词，意为“无论多么。No matter how cold it is，he still works outdoors.5wh­

14、;ever等一系列连词既可引导让步状语从句相当于no matter wh­，也可引导名词性从句。而no matter wh­只能引导让步状语从句，不能引导名词性从句。No matter/Whatever what happened，he would not mind. 目的状语从句目的状语从句可以由表示“为了， 以便的so that有时省略so， in order that和表示“以免， 以防的lest， for fear that， in case引导lest， for fear that后的目的状语从句一般要用“可以省略的should动词原形的虚拟语气形式； in ca

15、se后的目的状语从句多用虚拟语气，但也可用陈述语气。I will not make a noise lest I should disturb you. 我不出声，以免打搅你。He is working hard for fear that he should fail. 他认真学习，以免考不及格。Take your umbrella in case it rains. 带上雨伞， 以防下雨。假如表示“为了，以便的目的状语从句的主语与主句的主语一样，可用in order to或 so as to取代该目的状语从句： He hurried through his work in order to

16、 catch the train. 他匆匆干完手中的活，为的是能赶上火车。结果状语从句结果状语从句表示结果， 通常位于主句之后。1. so that可以引导目的状语从句， 也可以引导结果状语从句。It was very cold, so that the river froze.天气寒冷，河水都结冰了。so that引导结果状语从句I came to the class early so that I could see the classmate beside me. 我赶早来上课，以便早点看到我旁边的同学。so that引导目的状语从句2. 表示“如此以致的“so. that.和“such

17、. that.均可引导结果状语从句， 其中的such 是形容词，修饰名词；so 是副词，修饰形容词或副词，详细的搭配形式是：1“soadj./adv.that/“soadj.a/ann.that；2“sucha/anadj.n.that。so foolish那样愚蠢 such a fool 这么个蠢货 so nice a flowersuch a nice flower so many / few flowers such nice flowersso much / little moneysuch rapid progress so many peoplesuch a lot of peop

18、le so many 已成固定搭配，a lot of虽相当于many，但a lot of只能用such搭配。 He speaks so fast that no one can catch him. 他说话太快，无人听得明白。There is so rapid an increase in population that a food shortage is caused. 人口增长如此迅速， 以致造成了粮食短缺。Our country has so much coal that she can export large quantities. 我们国家的煤炭非常丰富，可以大量出口。so与表示

19、数量的代词many，few，much，little等连用已经形成固定搭配， 这些场合下不能换用such的对应构造表示 假如结果状语从句的主语与主句的主语一样，可用so adj./adv. as to取代该结果状语从句， 注意体会以下例句： The weather was bad, so as to make a good photo hard to take. 天气恶劣， 以致难以拍出来好照片。He was so kind as to phone for a taxi for the patient. 他是如此热心，以致于他为病人打 叫了出租车。How could you be so stupid as to believe him? 你怎么这么笨，竟相信了他的话？地点状语从句地点状语从句主要用于答复Where?的问题，可以由where 在的地方，wherever 无论什么地方等连词来引导。where, wherever指详细地点时，从句可用于主句之前或之后；表示抽象条件的含义时，从句