7.4 状语从句

状语从句概述

英语中的状语从句有九大类，分别表示：时间、地点、原因、目的、结果、条件、让步、比较、以及方式。尽管种类较多，但理解起来并不难。

本质上，状语从句就是用连词将两个分句连接起来，以表达分句之间特定的逻辑关系。

a. I’ve brought my umbrella in case it rains.
b. i’ve brought my umbrella because it’s raining.
c. i’ve brought my umbrella so that I don’t get wet.
d. i’ve brought my umbrella even though It’s not raining.
e. i’ve brought my umbrella unless it rains.

因此，学习状语从句的关键是要掌握引导九类状语从句的连接词。只要记住连接词及其表示的主从句关系，就能识别是何种状语从句，从而正确分析句子结构并理解句子意思。

状语从句	常用连接词
时间状语从句	when, while, as, before, after, since, till, until, as soon as
地点状语从句	where
原因状语从句	because, as, for, since
目的状语从句	so that, in order that
结果状语从句	so…that, so that, such…that
条件状语从句	if, unless
让步状语从句	although, though, even though, even if
比较状语从句	as, than
方式状语从句	as, the way

状语从句类型详解

状语从句：句子用作状语时，起副词作用的句子。根据其作用可分为时间、地点、原因、条件、目的、结果、让步、方式和比较等从句。状语从句位于句首或句中时通常用逗号与主句隔开，位于句尾时可以不用逗号隔开。

• When you are free, you can have a visit to my house.
• You can have a visit to my house when you are free.

时间状语从句：通常由when，as，while，after，before，since，as soon as，since，till（untill），while，once等词引导。

• I won’t leave untill you comes back.
• Once you see her, you will never forget her.
• Tom burst into laugh as soon as he received the information.
• 注意：1. 在时间状语从句中，主句是一般将来时，从句通常用一般现在时表示将来。
  • We’ll go fishing if it doesn’t rain tomorrow.
  • I’ll write to you as soon as I get to Beijing.
• 2. 结构hardly…when/no sooner…than和as soon as都可以表示”一…就…”的意思。如果hardly或no sooner置于句首，句子必须用倒装结构。
  • I had hardly got home when it began to rain.
  • I had no sooner got home than it began to rain.
  • As soon as I had got home, it began to rain.
  • Hardly had I got home when it began to rain.
  • No sooner had I got home than it began to rain.

1. 比较while，when，as
   • as，when引导短暂性动作的动词，while一般引导延续性动作的动词。
     • Just as/Just when/When I stopped my car, a man came up to me.
     • My wife was doing housework while I am watching TV.
     • He was talking to my partner when I came in.
   • 从句表示“随时间推移”连词能用as，不用when或while。
     • As the day went on, the weather got worse.
2. 地点状语从句：通常由where和wherever来引导。
   • Go back where you came from!
   • I make up my mind to find her wherever she may be.
   • Tom often make a mark in the practice book where he has a question.
3. 原因状语从句：表示原因或理由，引导这类从句的最常用的连词是because，since，as，nowthat等，for表示因果关系时（它引导的不是从句）为并列连词。
   • She was angry because her child disappointed her.
   • As it is raining, I decide to stay at home.
   • Now that you mention it, I will do my best to help him.

1. 目的状语从句：在句中做目的状语，最常用的引导词是so that，in order that，in case（以防，以免）等。
   • You must speak clearly so that/in order that you can make you understood.
   • You had better take an umbrella in case it rains.
2. 结果状语从句：表示事态结果的从句，通常主句是原因，从句是结果。由so…that，such…that引导。
   • Tom was so excited that he could not say a word.
   • Miss Zhang is such a good teacher that everyone respects her.
   • so…that与such…that之间可以根据句意内容转换。
   • The middle school student is so naughty that his mother often scolds him.
   • The middle school students is such a naughty boy that his mother often scolds him.
3. 条件状语从句：连接词主要有if，unless，as long as。if引导的条件句有真实条件句和非真实条件句两种。
   • If he is not in the office, he must be out for dinner.
   • I will give you everything as long as you love me.
   • Tom will have a visit to White House if he is the top student in this test.
   • 注意：1. 条件状语从句也符合主将从现的原则。
   • 2. 条件状语从句中if不能用whether来替换。
   • 3. unless=if not
     • We will have a break unless you are not tired.
     • If you are tired, we will have a break.

1. 让步状语从句：
   • though，although引导的让步状语从句，后面的从句不能有but。
     • Although/Though it’s raining, the farmers are still working in the field.
   • as引导的让步状语从句一般是倒装的。
     • Though he is a child, he knows what is the right thing to do.
     • Child as/though he is, he knows what is the right thing to do.
   • ever if, even though 即使
     • We’ll go outing even though the weather is bad.
     • Even if it should rain tomorrow, we will continue doing our research.
   • whether…or…不管······都。
     • Whether you believe it or not, it is true.
   • “no matter+疑问词”或“疑问句+后缀ever”：
     • no matter what = whatever
     • no matter what = whoever
     • no matter what = whenever
     • no matter where = wherever
     • no matter which = whichever
     • no matter how = however
     • No matter what happened, he would not care.
     • =Whatever happened, he would not care.
     • 注意：”no matter+疑问句“不能引导主语从句和宾语从句。
       • 判断对错：
       • No matter what you say is of no use now. 【错】
       • Whatever you say is of no use now.【对】
       • Prisoners have to eat no matter what they’re given.【错】
       • Prisoners have to eat whatever they’re given.【对】