高中英语状语从句用法详细解析
一、定义：
在句中作状语的从句是状语从句，修饰主句中的动词、形容词或副词等。状语从句由从属连词引导，从属连词在句中不充当句子成分，只起连接作用，状语从句放在句首时，要用逗号，放在句尾时不用。
二、分类
根据意义上的不同，状语从句可分为：①时间状语从句②地点状语从句③原因状语从句④目的状语从句⑤条件状语从句⑥结果状语从句⑦让步状语从句⑧方式状语从句⑨比较状语从句
三、时间状语从句
（一）引导时间状语从句的连词有：as, when(whenever), before, after, as soon as, until(till), since, every time, once.
（二）、“as” as, when, while都有“当……的时候”，可以互用When she was a child.
While she was a child. She Lived in Paris.
As she was a child.
as有“一边…一边”的意思
He sang as he walked.
“when”
When the clock struck twelve, all the lights went out.
I was sleeping when she came in. 动补
When we arrived at the station, the train had left.
“while” 主、从句动作或状态同时发生。用while引导的从句用延续性动词，常表示较长的时间或一个过程。
While we were having supper, all the lights went out.
Please keep quiet while others are studying.
While I was writing letters last night, he was watching TV.
when, while并列连问。when和while都可用作并列连问，连接并列分句。When表示“就在……的时候”, while意反而，可是，表示转折。
One evening Beethoven was walking in a street, when he suddenly stopped outside a little house.
并列连词引导并列句，意思是就在那时。
（三）、主句是一般将来时，时间状语从句用一般现在时表将来，主句是过去将来时，从句用一般过去时表示过去将来时，主句是一般过去时，从句用一般过去时。
1. I' ll call you when I get there.
2. They said they would leave when they got the new.
3. They left as soon as they got the new.
Whenever 无论什么时候，随时
1. Whenever someone throws in some rubbish, the truck produces a piece of music.
每当有人扔进一些垃圾时，它（汽车）就放一段音乐。
2. Whenever we' re in trouble, they will help us.
3. I go to the theatre, whenever I am free.
4. Come and see me whenever you want to.你随时来看我。
till和until(表示“直到……”)句首多用until
1、在肯定句中表示“直到……为止”，主句谓语动词要用延续性动词。
I was waiting until/till he arrived.
2、在否定句中表示“直到……才”主句谓语动词常用终止性动词，这时until和till常被before替换。
I didn' t leave till/until she came back.
since: 主句用完成时，从句用一般过去时，since引导的从句间或可用现在完成时。
It is two years since I have studied English.
1. We have known each other since we were children.
2. We have been friends (ever since) since we met at school.
3. It is …… (一段时间)+since+一般过去时态句子。
It is two years since my sister married.
……(一段时间) have/has passed since +一般过去时态句子
Two sisters have/has passed since my sister married.
Since+时间点
1. I have been at home since three o' clock this afternoon.
2. Maria has been in China since two years ago.
*every time, each time, next time
Every time you get back at night, you drop your boots on the floor. Every time I catch cold, I have pain in my back.
(every time 分写不可以合写) 比较everyday (adj) 日常的，普通的every day 是名词短语，每天，天天
Next time I go there, I will visit them.
* once 一旦…就
Once you begin, you must go on. 你一开了头，就应该继续下去。
四、地点状语从句
地点状语从句用where, wherever引导
We should go where the people need us.我们应该去人民需要我们的地方。
Where there is a will, there is a way. 有志者，事竟成。Wherever they went, they received a worm welcome.
无论他们走到哪儿都受到热烈欢迎。
She follow him whose he goes. 他无论到哪里她总跟着。
五、原因状语从句
原因状语从句用because(因为)，since(既然), as(由于)引导
1、字母由多到少，语气由强到弱。
2、由why提问必须用because回答。
Since, as不回答why的提问，而且从句一般放在句首，because一般放在主句之后。
3、 before of +名词
Because of the rain, we didn' t go to the park.
4、 because 和so不可连用，只能选其一。（另有although, but）Why didn' t he come to school? Because he was ill.
Since I must die, I must. 既然我一定要死，我一定这样做。
Since a lot of people make mistakes in life, Mr Smith wanted to give John a Chance.
