Once you show any fear, he will attack you.

We had hardly got / Hardly had we got into the country when itbegan to rain.

No sooner had he arrived / He had no sooner arrived than she started complaining.

③directly, immediately, the moment, the minute that... 一......就

He made for the door directly he heard the knock.

④each time, every time, by the time

Each time he came to my city, he would call on me.

注意：表示未来情况，主句用将来时，从句用现在时。

2、让步状语从句

（1）although与though可以引导让步状语从句，不能与but连用，但可以与yet连用。

Although they are poor,(yet)they are warm-hearted.

（2）even if或even though引导让步状语从句，表示"即使"，"纵然"，用来使人注意下文所强调内容的性质。

I'll get there even if(though)I have to sell my house to get enough money to go by air.

（3）no matter后接上who、what、where、how等疑问词，也可以在这类疑问词后面加上ever构成whoever、whatever、wherever、however等。

Don't trust him, no matter what / whatever he says.

Whoever breaks the law will be published.

No matter how hard the work is, you'd better try to do it well.

（4）as也可以引导让步状语从句。要用倒装。

Child as(though)he is, he knows a lot.

Much as I like it, I won't buy.

Try as he would, he couldn't lift the heavy box.

3、原因状语从句：because, for, as, since, now that

项目 区别 位置 内涵 语气 能否回答why because因为 主句前或后 直接的因果关系 强 能 as由于 : 主句前或后 双方都知道的原因 弱 不能 since/ now that既然 主句前 for因为（并列连词） 主句后 推断的因果关系 下列情况下只能使用because:

①在回答why的问句时；

②在用于强调句型时；

③被not所否定时。例如：

My friends dislike me because I'm handsome and successful.

　　Now that everybody has come, let's begin our conference.

　　The higher income tax is harmful in that it may discourage people from trying to earn more.

　　Considering that he is no more than 12 years old, his height of 1.80 m is quite remarkable.