状语从句是什么

　　状语从句指句子用作状语时，起副词作用的句子。状语从句中的从句可以修饰谓语、非谓语动词、定语、状语或整个句子。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。

　　状语从句一般由连词(从属连词)引导，也可以由词组引起。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。

　　状语从句分类

　　一、时间状语从句

　　I didn’t realize how special my mother was until I became an adult.

　　直到我成为了一个成年人我才意识到我的母亲是多么的特殊。

　　While John was watching TV, his wife was cooking.

　　当约翰看电视时，他的妻子正在做饭。

　　二、地点状语从句

　　Generally, air will be heavily polluted where there are factories.

　　有工厂的地方空气污染就严重。

　　Wherever you go, you should work hard.

　　无论你去哪里，你都应该努力工作。

　　三、原因状语从句

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

　　我的朋友都不喜欢我，因为我又英俊又成功。

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

　　既然每个人都到了，让我们开始我们的会议吧。

　　四、目的状语从句

　　The boss asked the secretary to hurry up with the letters so that he could sign them.

　　老板要求秘书快写函件以便他能在上面签字。

　　The teacher raised his voice on purpose that the students in the back could hear more clearly.

　　为了让后面的学生听得更清楚，老师有意地提高了他的声音。

　　五、结果状语从句

　　He got up so early that he caught the first bus.

　　他很早起床以便赶上第一班公共汽车。

　　It’s such a good chance that we must not miss it.

　　这是一个好机会，千万不能错过它。

　　六、条件状语从句

　　We’ll start our project if the president agrees.

　　如果总统同意，我们将开始我们的项目

　　You will certainly succeed so long as you keep on trying.

　　只要你继续努力，你一定会成功的。

　　七、让步状语从句

　　Much as I respect him, I can’t agree to his proposal.

　　尽管我很尊敬他， 但是我却不同意他的建议。

　　The old man always enjoys swimming even though the weather is rough.

　　老人都很喜欢游泳，即使天气很恶劣。

　　八、比较状语从句

　　She is as bad-tempered as her mother.

　　她和她妈妈一样脾气很坏。

　　The house is three times as big as ours.

　　这房子是我们的三倍大。

　　九、方式状语从句

　　When in Rome, do as the Romans do.

　　入国问禁，入乡随俗。

　　She behaved as if she were the boss.

　　她表现得好像她是老板。