2.引导条件状语从句的从属连词，这类连词主要有if, unless, as [so] long as, in case 等。如：
Do you mind if I open the window?我开窗你不介意吧?
Don’t come unless I telephone. 除非我打电话，否则你别来。
As long as you’re happy，it doesn’t matter what you do. 只要你高兴，你做什么都没关系。
In case it rains they will stay at home. 万一下雨，他们就呆在家里。
注意：在条件状语从句中，通常要用一般现在时表示将来意义，而不能直接使用将来时态。不过，有时表示条件的 if之后可能用 will，但那不是将来时态, 而是表示意愿或委婉的请求(will为情态动词)。如：
If you will sit down for a few moments, I’ll tell the manager you’re here. 请稍坐, 我这就通知经理说您来了。
3. 引导目的状语从句的从属连词。主要的有 in order that, so that, in case, for fear等。如：
He raised his voice so that everyone could hear. 他提高了嗓音，以便每个人都能听见。
Take your umbrella (just) in case it rains. 带上雨伞，以防下雨。
She repeated the instructions slowly in order that he should understand. 她把那些指示慢慢重复了一遍好让他听明白。
4. 引导结果状语从句的从属连词。主要的有so that, so…that, such…that等。如：
I went to the lecture early so that I got a good seat. 我去听演讲去得很早, 所以找个好座位。
I had so many falls that I was black and blue all over. 我摔了许多跤，以致于全身都是青一块紫一块的。
He shut the window with such force that the glass broke. 他关窗子用力很大, 结果玻璃震破了。
5. 引导原因状语从句的从属连词。主要的有because, as, since, seeing (that), now (that), considering (that) 等。如：
He distrusted me because I was new. 他不信任我，因为我是新来的。
As you are sorry，I’ll forgive you. 既然你悔悟了，我就原谅你。
Since we’ve no money, we can’t buy it. 由于我们没钱，我们无法购买它。
Seeing that he’s ill he’s unlikely to come. 因为他病了，他大概不会来了。
Now that she has apologized, I am content. 既然她已经道了歉, 我也就满意了。
6. 引导让步状语从句的从属连词。主要的有although, though, even though, even if, while, however, whatever, whoever, whenever, wherever等。如：
Although they are twins, they look entirely different. 他们虽是孪生, 但是相貌却完全不同。
I like her even though she can be annoying. 尽管她有时很恼人, 但我还是喜欢她。
You won’t move that stone, however strong you are. 不管你力气多大, 也休想搬动那块石头。
Whatever we have achieved, we owe to your support. 我们取得的一切成就都归功于你们的支持。
Whoever you are, you can’t pass this way. 不管你是谁，你都不能从这里通过。
Whenever I see him I speak to him. 每当我见到他，我都和他讲话。
7. 引导方式状语从句的从属连词。主要的有as, as if, as though, the way等。如：
Why didn’t you catch the last bus as I told you to? 你怎么不听我的话赶乘末班公共汽车呢?
He bent the iron bar as if it had been made of rubber. 他将铁棍折弯，仿佛那是用橡皮做成的。
Nobody else loves you the way(=as) I do. 没有人像我这样爱你。
8. 引导地点状语从句的从属连词。主要的有where, wherever, everywhere, anywhere等。如：
The church was built where there had once been a Roman temple. 这座教堂盖在一座罗马寺庙的旧址。
I’ll take you anywhere you like. 你想到哪儿我就带你到哪儿。
Everywhere I go，I find the same thing. 不管我走到哪里，我都发现同样情况。
9. 引导比较状语从句的从属连词。主要的有than和as…as。如：
She was now happier than she had ever been. 现在她比过去任何时候都快活。
I glanced at my watch. It was earlier than I thought. 我看了看表，时间比我想像的早。
He doesn’t work as hard as she does. 他工作不像她那样努力。
10. 引起名词从句的从属连词。主要有that, whether, if 等，它们用于引导主语从句、表语从句、宾语从句和同位语从句。其中that 不仅没不充当句子成分，而且没有词义，在句子中只起连接作用;而 if, whether 虽不充当句子成分，但有词义，即表示“是否”。如：
He replied that he was going by train. 他回答说他将坐火车去。
I wonder if it’s large enough. 我不知道它是否够大。
I worry about whether I hurt her feelings. 我为是否伤了她的感情而担心
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