状语从句

　　在复合句中, 起状语作用的从句称作状语从句。

　　根据语义, 状语从句分为:

　　时间状语从句、地点状语从句、条件状语从句、原因状语从句、

　　让步状语从句、比较状语从句、目的状语从句、结果状语从句、

　　方式状语从句。

　　状语从句可放在句首或句末。如状语从句位于主语前,一般用逗号将其与主句隔开。

　　(一)时间状语从句

　　When you cross a main road, you must be very careful.

　　Until we learn the facts, we can’t do anything about it.

　　[提示]

　　1. when, as, while引导时间状语从句时都可以表示主句的动作与从句的动作同时发生, 即同时性。它们的区别在于:

　　when和as引导的状语从句中的动作既可以是延续性的, 也可以是非延续性的, 即瞬时性的;

　　while引导的状语从句中的动作只能是延续的动作或状态。

　　当主句和从句中的动作均为延续动作时, 一般用while, 而不用when或as。当表示两个同时发展、变化的情况时, 一般用as, 作“随着…”解。

　　When she comes, I shall tell her to wait for you.

　　As she got older, she got wiser.

　　While Peter was reading, his wife was cooking.

　　2. 有些副词和一些表示时间的名词词组也可用作从属连词,引导时间状语从句。如instantly, immediately, directly, the day, every time, the minute, the second, the moment等。

　　Immediately he arrived, he started describing us what had happened.

　　The day he returned home, his grandpa was already dead.

　　(二)条件状语从句

　　引导条件状语从句的从属连词有:

　　if, unless, as (so) long as, only if(只要)。

　　If you don’t come on time, we’ll start out without you.

　　As (so) long as you keep on trying, you’ll certainly succeed.

　　[提示]

　　除了以上提到的从属连词外, 还有其它的一些词或词组也可引导条件状语从句。

　　如: providing that, provided, supposing that, suppose that, on condition that, in case等。

　　Provided (that) he wins the support of the minority groups, he will be able to win the election.

　　I will go providing that my expenses are paid.要是我的费用有人代付我就去

　　Supposing he is not at home, what then? 假如他不在家,那怎么办?

　　You can use the bicycle on condition that you return it tomorrow.只要你明天归还,自行车你可以拿去用。

　　In case she comes back, let me know immediately.假使她回来了,立刻告诉我

　　Take the raincoat in case it rains.带着雨衣,以防下雨。

　　(三)原因状语从句

　　引导原因状语从句的从属连词有: because, since, as, now(that), in that, considering that等。

　　Since the speaker can’t come, we’ll have to cancel the meeting.

　　Considering he’s only been learning English a year he speaks it very well.考虑到他只学了一年英语,他讲得算是很流利了。

　　We didn’t know what to do as we were just visiting there.我们不知道该怎么办,因为当时我们仅仅在那里作访问。

　　Since it is so hot, let’s go swimming.既然天气这么热,我们去游泳吧。

　　[提示]

　　in that和now(that)的用法: in that引导的从句对主句进行解释和说明,意思是: 在…方面, 在于…; 因为。now(that)表示既然。

　　Theory is valuable in that it can provide a direction for practice.

　　理论所以有价值,就在于它能给实践指出方向。

　　Now (that) the weather has improved, let’s go out for a picnic.

　　既然天气已转好, 我们就出去野餐吧。

　　(四)让步状语从句

　　引导让步状语从句的从属连词有: though, although, even if (even though), as, no matter…despite the fact that, in spite of the fact that, while。

　　Tom always enjoys swimming, even though the weather is rough.

　　Despite the fact that there exists national differences, certain funny situations have a universal appeal.

　　Tired as he was, he sat up late.他虽然疲倦,可仍然很晚才睡。

　　No matter how they slander us, we will never give in.不管他们怎样诽谤我们,我们决不让步。

　　While I like the color of the hat, I do not like its shape.虽然我喜欢这顶帽子的颜色,但我不喜欢它的形状。

　　[提示]

　　一些疑问词在词尾加上ever后, 也可引导让步状语从句,相当于no matter+疑问词。这些词包括: whatever, wherever, whenever, whoever, however。

　　Whatever he says, don’t believe him.

　　Whoever you are, you must obey the traffic regulations.

　　(五)目的状语从句

　　引导目的状语从句的从属连词有: so that, in order that, lest, in case, for fear that。

　　They climbed to the top of the building in order that they could get a bird’s-eye view of the city.

　　Ask her to hurry up with these letters so that I can sign them.

　　We dare not play jokes on him lest he should become angry.我们不敢开他玩笑生怕他动气。

　　[提示]

　　so that和in order that的区别: so that更常用, in order that更正式。so that引导的从句一般置于句末,而in order that引导的从句既可置于句首, 又可置于句末。

　　In order that the grass and flowers could bloom again, it was necessary that the rocks should be removed.

　　She got up early so that she could catch the first bus.

　　(六)结果状语从句

　　结果状语从句一般由下列连词引导: so that, so…that, such…that。

　　He overslept, (so) that he was late for work.

　　They got such a fright that they dropped the bag and ran away.

　　[提示]

　　1. so…that和such…that的区别。so后接形容词或副词, such后接名词。

　　It was so cold that we had to cancel the game.

　　It’s such a good chance that we mustn’t miss it.

　　2. so that既可引导目的状语从句, 也可引导结果状语从句。so that引导目的状语从句时, 一般从句动词前会出现can(could),may(might),shall(should),而so that引导的结果状语从句表示客观事实, 不会出现上述词语。

　　引导结果状语从句的so that前常有逗号, 表示强调。so that引导的目的状语可置于句首,而so that引导的结果状语从句只能置于句末。

　　He left early so that he could catch the train.

　　他早早动身, 以便能赶上车。(目的)

　　He left early, so that he caught the train.

　　他早早动身, 赶上了火车。(结果)

　　(七)方式状语从句

　　引导方式状语从句的从属连词有as, as if(though), the way, how。

　　He made some changes as you had suggested.

　　She was behaving as if (though) she hadn’t grown up.