1、专题2 原因状语从句【例句及用法】原因状语从句指在句中用来说明主句原因的从句。引导原因状语从句的从属连词有because（因为）， as（由于）， since（既然），now(that)（既然）， when（既然）， seeing (that) （由于，鉴于），considering (that)（考虑到），for（因为），given (that) （考虑到）等。例句：1. The woolly shrank because it was washed badly.毛衣因为洗涤的方法不好而缩水。2. Since (As) weve no money, we cant buy it.由于我们没钱
2、，我们不能购买它。3. Now that you are here, youd better stay.你既然来了，最好还是留下吧。【考点1】when表示“既然”I wont tell you when you wont listen. 既然你不想听，那我就不告诉你了。【考点2】关于“notbecause.”结构的理解在没有特定上下文时会有歧义，例如：I didnt go because I was afraid. 我没有去是因为怕。/ 我不是因为怕才去的。不过若because之前有just修饰，一般认为not 是否定从句的：You shouldnt get angry just becaus
3、e some people speak ill of you.你不要因为有人说你坏话而生气。【考点3】because不能与so连用正：Because it was raining, we stayed at home. / It was raining, so we stayed at home.误：Because it was raining, so we stayed at home.【考点4】because与 because of的转换1. He cant come because he is ill. / He cant come because of his illness.他因病不
4、能来。2. I said nothing about it because his wife was there. / I said nothing about it because of his wifes being there.因为他妻子在那儿，我对此事只字未提。【考点5】since引导原因状语从句since引导的原因状语从句一般放于主句之前，通常被翻译成“既然”（= now that )， 语气比because弱。例如：1. Since you are free today, you had better help me with my mathematics.2. Since you
5、 dont trust him, you should not employ him.3. Now (that) you are grown up, you should not rely on your parents.【考点6】as 引导原因状语从句as 引导原因状语从句时含有对比说明的意味，语气比since弱， 较为正式，位置较为灵活（常放于主句之前）。1. As it is raining, youd better take a taxi. 因为下雨了，你最好打车。2. As you are tired, you had better rest. 因为你累了，最好休息一下。3. I w
6、ent to bed early, as I was exhausted. 我很早就睡了，因为我筋疲力尽了。【考点7】as 引导表示原因的分句for引导的是并列句表示原因但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引导的并列句只能放于前一个分句之后并且必须用逗号将它们隔开。1. He could not have seen me, for I was not there.2. He seldom goes out now, for he is very old.【考点8】seeing (that)， now (that)， considering (that)， in
7、 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”。例句：1. Seeing (that) he refused to help us, theres no reason that we should now help him.他既然曾经拒绝帮助我们， 我们没有理由要来帮助他。2. Now (that) you are grown up, you should not rely on your parents.既然你长大了， 就不应该依靠你的父母了。3. Considering (that) everybody is here, lets begin our disc
8、ussion.既然大家都到了， 我们就开始讨论吧。4. In that he is ill, he feels unable to do it.因为他生病了，他觉得做不了那件事。【考点9】原因状语从句与原因状语的转化原因状语没有使用从句来充当时，依然可以表达同样的作用和意义，可以通过从句的角度去理解，例如第一种情况，以下类同。1.形容词作原因状语Thirsty,he went to the teahouse for a drink first.因为渴了，他先到茶社里去喝点水。（Thirsty相当于Because he was thirsty）Afraid of being late, they
9、 came by taxi.因为怕迟到，所以他们坐出租车来的。（Afraid of being late相当于Because he was afraid of being late）2.介词短语作原因状语我们可以用at, for, from, of , with, etc.介词引导的短语作原因状语，例如：He felt uneasywith the whole class staring at him.全班同学瞧着他，他感到很不自在。I was overjoyedat the news of your success.获悉你成功的消息，我特别高兴。Thank youfor reminding
10、me in time.谢谢你及时提醒我。He looked very tiredfrom lack of sleep.由于缺乏睡眠，他显得很疲倦。Seeing her win the gold medal at the Olympics, we were all wildwith joy.看到他在奥运会上赢得了金牌，我们真是欣喜若狂。He was lateas a result of the traffic jam.由于交通阻塞，他迟到了。Out of curiosity,he unpacked the magic bag.出于好奇，他把那个魔术盒打开了。3.分词短语作原因状语Not havi
11、ng got enough hands, we had difficulty in completing the work in time.由于人手不够，我们很难按时完成任务。Excited at the moment,she went to London alone.由于心血来潮，她独自去了伦敦。Sent back home,the old man got to calm down.因为被送回了家，老人才慢慢平静了下来。4.独立结构作状语Her house destroyed by the rainstorm,he had to live in the cave.由于房子被暴风雨冲毁，Tha
12、t being the case,well have to reconsider the whole plan.情况就是这样，所以我们只得重新考虑整个计划。【高考回放】1._ youve got a chance, you might as well make full use of it. A. Now that B. After C. Although D. As soon as答案 A解析 主句与从句之间存在因果关系， 且“youve got a chance”表示一个显而易见的原因，因此应选用表原因的now that。2. He found it increasingly diffic
13、ult to read, _ his eyesight was beginning to fail.A. and B. for C. but D. or答案 B解析 “his eyesight was beginning to fail”是“he found it increasingly difficult to read”的原因， 因此本题应选用可以表示原因的连词for引导原因状语从句。3. A man cannot smile like a child, _ a child smiles with his eyes, while a man smiles with his lips al
14、one.A. so B. but C. and D. for答案 D解析 下划线处之后的句子补充说明“a man cannot smile like a child”的原因，应选用for表原因。【对点练习】一、在下列句子的空格中填入适当的连词，每空一词。1. _ Jane was the eldest, she looked after the others.2. _ you know it, I wont repeat it.3. He didnt hear the knock at the door _ he was listening to the radio.4. Why didnt
15、you come? _ my father wouldnt let me.5. _ _ everybody is here, lets begin the discussion.二、句型转换。把从句简化为 because of 结构：1. He lay in bed because he had caught a bad cold.2. He couldnt walk because his leg was broken.3. I came back because it was raining.4. They stayed in because the weather was bad.5.
16、We didnt get home till after midnight because we had missed the bus.把从句简化为分词短语：6. As he is a warmhearted man, he is always ready to help others.7. As he saw nobody in, he decided to leave a note.8. Because he didnt understand its meaning, he asked the teacher to explain the word.9. As he had lived i
17、n Beijing for many years, he knew the city very well.10. As I have not seen the film, I cant tell you what I think of it.11. As they were influenced by Lei Fengs example, they did a lot of good deeds.12. As he was brought up in the countryside, he was not used to the city life.把从句简化为形容词短语：13. Becaus
18、e he was afraid of being late for class, Bob ran to school as fast as he could.14. As he was full of ear, Crusoe left the cave in a hurry.15. As he was anxious for a quick decision, the chairman called for a vote.【参考答案】一、 1. As 2. Since 3. because 4. Because 5. Now that/Seeing that二、1. He lay in bed
19、 because of a bad cold.2. He couldnt walk because of his broken leg.3. I came back because of the rain.4. They stayed in because of the bad weather.5. We didnt get home till after midnight because of missing the bus.6. Being a warm-hearted man, he is always ready to help others.7. Seeing nobody in,
20、he decided to leave a note.8. Not understanding its meaning, he asked the teacher to explain the word.9. Having lived in Beijing for many years, he knew the city very well.10. Not having seen the film, I cant tell you what I think of it.11. Influenced by Lei Fengs example, they did a lot of good deeds.12. Brought up in the countryside, he was not used to the city life.13. Afraid of being late for class, Bob ran to school as fast as he could.14. Full of ear, Crusoe left the cave in a hurry.15. Anxious for a quick decision, the chairman called for a vote.6
