状语从句是副词性从句，它在句子中担任状语，修饰主句的动词、形容词或副词。根据修饰的方面，状语从句可以分为以下九种。
1、时间状语从句
2、地点状语从句
3、原因状语从句
4、目的状语从句
5、结果状语从句
6、条件状语从句
7、方式状语从句
8、 让步状语从句
9、 比较状语从句
1、时间状语从句
种类 从属连词 例 句 说 明
时 when
whenever When I came into the room, he was writing a letter.
当我进屋时，他正在写信。
We shall go there whenever we are free.
我们什么时间有空，我们就去那里。
when指的是“某一具体的时间”。
whenever指的是“在任何一个不具体的时间”。
间
状 when I was walking along the street when suddenly someone patted me on the shoulder from behind.
我正在街上走着，这时忽然有人从后面拍我的肩膀。 when意为“这时”或“在那个时候”,可以看作是并列句,这种用法的when分句一般位于句末。
语
while While it was raining, they went out.
天下雨的时候，他们出去了。
I stayed while he was away.
他不在的时候我在。 while指“在某一段时间里”，“在…期间”，while引导的动作必须是持续性的。
从
as He hurried home, looking behind as he went.
他赶快回家，不时地一边走一边向后看。 as引导持续性动作，强调主句和从句的动作同时发生。
句 before Be a pupil before you become a teacher.
先做学生，再做先生。 before译为在…之前
after He arrived after the game started.
比赛开始后，他到了。
till We waited till (until)he came back .
我们一直等到他回来。 如主句动词是持续性动作，常用肯定式，表示“直到…为止”
种类 从属连句 例 句 说 明
时 until She didn’t stop working until eleven o’clock .
她到11点钟才停止工作。
Until he had passed out of sight, she stood there.
她站在那里看着，直到看不见他的身影。 如主句动词是瞬间动词，常用否定式，表示“直…才”“在…以前不”,从句放在句首表示强调，一般用until
间
状
since
as soon as
Great changes have taken place in China since 1978.
自从1978年以来中国发生了巨大的变化。
As soon as I arrive in Shanghai, I’ll write to you.我一到上海就给你写信。 状语从句在主句之前时一般用逗号与主句分开，如从句在主句之后则不必用标点符号。
语
从
句 hardly…when
no sooner…than
I had hardly got home when it began to rain.
我刚一到家，就下雨了。=Hardly had I got home when it began to rain.
No sooner had we got to the station than the train left.
我们刚到车站，火车就走了。
Hardly had we begun when we were told to stop.
我们刚开始就被叫停。 hardly…when和no sooner…than的意义相当于as soon as,但只表示过去发生的事情，主句为过去完成时，从句为过去时，如hardly或no sooner位于句首时语气强，而且主句的谓语要用部分倒装。
every time, by the time, the moment
等 Every time I travelled by boat, I got seasick.
我每次乘船都晕船。
The moment I heard the song, I felt cheerful.
我一听到这首歌，就感到很愉快。
Next time you come ,you’ll see him.
下次你来的时候，就会见到他。 在时间状语从句中，不能用将来时或过去将来时，而要用现在时或过去时代替将来时。
地
点
状
语
从
句 where
wherever Where there is a will, there is a way.
有志者，事竟成。
Where there is water there is life.
哪里有水，哪里就有生命。
You are free to go wherever you like.
你可以随意到你喜欢的任何地方去。
Wherever you go, you must obey the law.
无论你去哪都要遵守法律。 where与wherever意义基本相同，但后者语气较强，多用于书面语。
原
因
状 because I came back late yesterday because I was on duty.
昨天我回来晚了，因为我值班。 because用来回答why 的问题，语气最强一般放在主句之后
语
从
句 since Since everyone is here, let’s begin our meeting.
既然大家都到了，我们开始开会。 since表示既然或全已知的理由,稍加分析即可表明的原因,多放句首
种类 从属连句 例 句 说 明
原
因 as As he didn’t know much English, he looked up the word in the dictionary .
由于他英语懂得不多，他在字典中查阅这个单词。 从句常放在句首，说明原因，主句说明结果，常用于口语中。
状
语
从
句 now that, seeing that Now (that) the weather has cleared up, we can start our journey.
鉴于天气已经晴朗，我们可以启程了。
Seeing (that) he was badly ill, we sent for the doctor.
鉴于他病情严重，我们派人去请医生去了。 seeing (that), now that 和since, as 意义相似，他们都有“鉴于某个事实”的意思，that可以省去。
目
的
状
语
从
句 that
so that
in order that
lest = for fear that I shall write down your telephone number that I may not forget.
我要把你的电话号码记下来，以免忘记。
We’ll tell you the truth so that you can judge for yourself.
我把真实情况告诉你，使你能自己作出判断。
They worked harder than usual in order that they could finish the work ahead of time .
他们比往常更加努力工作，为了能提前完成工作。
Put on more clothes lest (= for fear that ) you should catch cold.
多穿点衣服，以免患感冒。 目的状语从句中常用情态动词may (might) can (could) ,should 等放在动词之前，从句往往放在主句之后，主从句之间不用任何标点符号
结
果
状 so that
so…that We turned up the radio, so that everyone heard the news.
我们把收音机的音量放大，大家都听到了新闻。
He was so excited that he couldn’t say a word.
他十分激动，以致一句话都说不出来。 so that前有逗号为结果状语从句。
so…that的so后面跟形容词或副词。
语
从
句 such…that He gave such important reasons that he was excused.他说出了这么重要的理由，得到大家的谅解。
It is such an interesting novel that all of us want to read it.
It is so interesting a novel that all of us want to read it.
这是一本十分有意思的书，大家都想看。 such…that的such后面跟名词，如果名词是单数就要用such a /an…that还可以转换用so…that，语气较强
种类 从属连句 例 句 说 明
条
件
状
语
从
句 if
unless
as/so long as
in case
so far as Difficulties are nothing if we are not afraid of them.
如果我们不怕困难，困难就算不了什么了。
We shall go there tomorrow unless it rains.
除非下雨，我们明天就去那里。
= We shall go there tomorrow if it doesn’t rain.
So/As long as you work hard, you will succeed.
只要你努力工作，你就一定能成功。
In case I forget, please remind me about it .
万一我忘了，请提醒我一下。
So far as I know, the book will be published next month.
据我所知，那本书下月出版。
unless从句的谓语只能用肯定式。unless和if…not同义，unless是书面语，if…not是口语，通常二者可以换用。
条件状语从句中的谓语动词的时态一般要用现在时或过去时代替一般将来时或过去将来时。
方
式
状
语
从
句 as
as if…
as though Draw a cat as I taught you .
按照我教你的画一只猫。
Do as you are told.
按照人家告诉你做的去做。
She looks as if she is ill.
看上去她好象是生病了。
He acted as if (though) nothing had happened.
他的行动就好象什么也没有发生。
They treat the black boy as if (though) he were an animal.
他们对待这黑孩子仿佛他是一头牲口。 此处as译为，按照或正如
as if或as though的意义和用法基本一样。从句中可以用现在时表示可能符合事实，也可以用虚拟语气。
让
步
状
语 though
although Although (Though) he was over sixty, (yet) he began to learn French.
虽然他六十多岁了，但仍开始学习法语 。
We were not tired though (although) we had worked all day.
虽然我们干了一天活，但并不累。 在句子中一般用了“虽然”就不能再用“但是”（but）但可以与yet或still连用。though / although意义相同，用法基本一样，前者通俗，口语化，后者正式多放主句的前面。
从
句 even if
even though I’ll go even if (though) it rains tomorrow.
即使明天下雨，我也要去。 even if 和even though的意思为“即使”“纵使”有退一步设想的意味，多用于书面语中。
种类 从属连词 例 句 说 明
让
步
as Child as he is , he knows a lot .
虽然他是一个孩子，但他懂得很多。
Cold as it is, (= Though it is cold,)the children play outdoors.
虽然天气冷，但孩子们仍在户外玩。 as引出的状语从句多用于书面语，它比用
though或although引导的从句，语气强，更有表现力，从句常放在句首，语序部分倒装。
状
语
从
no matter (who, what when, where which, how…) Do it no matter what others say.
不管别人怎么说,尽管干。
No matter how busy he was, he studied English every day.
不管他多忙，他都每天坚持学习英语。
No matter who takes up the matter for me ,I shall be very grateful.
不管谁为我处理这件事，我都将非常感激。 no matter……与 who-ever引导的让步状语从句意义基本一 样，no matter……引导的从句可是以位于主句前或主句后。
句 wh－ever (whatever whoever whenever whichever however) Whatever happens / may happen , we shall not lose heart.
无论发生什么，我们都不要失去信心。
Whoever comes, he will be welcome.
无论谁来，都会受到欢迎。 wh－ever从句中的动词有时可以和may连用。判断wh－ever引导的是状语从句还是名词性从句的一点是，名词性从句，主句中一定有一个成分要在从句担任，一般从句与主句之间没有逗号。
不可将no matter与wh-ever连用
比
较
状
语 as…as
not so/as
…as
the same
…as
such…as Mary is as old as my sister.
玛利和我姐姐一样大。
He doesn’t run so (as) fast as Jack (does).
他不如杰克跑得那样快。
His book is the same as mine.
他的书和我的一样。
Henry is not such a good worker as Peter .
享利这个工人不如彼得那样好。 连词表示同程度级的比较，肯定句用as…as否定句可用not as…as 或not so…as
从
句 than She has made greater progress this year than she did last year.
她今年比去年进步更大。
He bought fewer books than I (did).
他买的书比我买的少。 表示不同程度之比较，主句中用比较级的形容词或副词。
种类 从属连句 例 句 说 明
比
较
状
语
从
句 the more
…the more The more you read, the better you understand.
你看的书越多，你懂得的就越多。
The more tickets you sell, the more money you will get.
你卖的票越多，你的收入也越多。
The harder you work, the greater progress you will make.
你工作越努力，你取得的进步就越大。
The sooner, the better.
越快越好。
The warmer, the better.
越暖和越好。 the more…the more 意思为越…越…，通常的语序为从句在前主句在后，这两个the都是表示程度的副词，用在比较级的形容词或副词前面。
句子意思明显，句子的主语和动词都可省略。
特
殊
形
式
的
状
语
从
句 that
We are sure (that )the four modernization will be realized in China .
我们相信四化一定会在中国实现。
I’m sorry (that) I didn’t have time to write you sooner.
很抱歉，我没有抽出时间早点给你写信。
I am afraid that I can’t go with you.
恐怕我不能同你一起去了。 that 引导的从句，往往跟在一个做表语的形容词后面，从句概念上看是宾语，所以有的语法家把它看做是宾语从句，但结构上看，也可以把它看作是一个特殊的状语从句，用来修饰表语的形容词。这种从句的连词常常被省略。