原因状语从句(学案).doc

原因状语从句
A、引导原因状语从句的连词
　 原因状语从句一般由从属连词because, as, since，now that引导。
B、because, as, since和now that的区别：
1、because“因为”，表示直接的原因，语气最强。
1）why提问的句子，必须用because回答。
2）because的从句常放在主句之后。
3）because 不能与so连用。
4）because+ 从句；because of+ 名词短语
I missed the train because I got up late.
He was angry not because we were late but because we made a noise.
-Why didn’t he come yesterday?  -Because he was ill.
2、as“因为”，语气较弱，一般放在主句前，中间用逗号隔开，表示的是明显的原因。
As he was not well, I decided to go there without him.
As it was raining hard, we had to be indoors.
3、since/ now that“既然”，一般放在主句前，中间用逗号隔开，表示的是明显的原因或众所周知的事实。
Since/ Now that this method doesn’t work, let’s try another.
Since/ Now that you feel ill, you'd better not go to work.
Exercise:
一、填入恰当的连词
1. I didn’t go to school yesterday _________ I was ill.
2. ________ everybody is here, let’s begin our meeting.
3. ________ you are in poor health, you should not stay up late.
4. I asked her to stay to tea, ________ I had something to tell her.
5. ________ all the passengers are here, why don’t we start at once?
6. Bill won’t make any progress ________ he doesn’t study harder than before.　　
二、 改写句子,保持句意不变
1) The ship changed its course because there was a storm.
The ship changed its course _______ _______ _______ _______.
2) Because he was ill, he didn’t go to school.
He was ill, _______ he didn’t go to school.
3) He couldn't walk because his leg was broken.
He couldn't walk ______ ______ his ______ leg.
4) I came back because it was raining heavily.
I came back ______ ______ the ______ rain.
三、 选择恰当的答案
1. The man can’t get on the bus ______ there is no room on it.
A. though B. because C. until D so that
2. ______ her daughter hadn’t come back, ______ she looked worried.
A. Because, / B. Because, so C. Though, but D. Though, /
3._______ you’ve got a chance, you might make full use of it.
A. Now that B. After C. Although D. As soon as
Keys：
A、引导原因状语从句的连词：because, as, since，now that
B、because, as, since和now that的区别：
1、because：“因为”，表示直接的原因，语气最强。
1）why提问的句子，必须用because回答。
2）because的从句常放在主句之后。
3）because 不能与so连用。
4）because+ 从句；because of+ 名词短语
2、as：“因为”，语气较弱，一般放在主句前，中间用逗号隔开，表示的是明显的原因。
3、since/now that：“既然”，一般放在主句前，中间用逗号隔开，表示的是明显的原因或众所周知的事实。
课堂练习：一、1.because 2.Since 3.As 4.because 5.Since 6.because
二、1.because of the storm 2. so 3. because of broken 4. because of heavy
三、1.B 2.A 3.A