状语从句的分类
一、时间状语从句
时间状语从句表示时间，引导词有：when, while, as, till, until before, after, since 等。
时间状语从句的引导词所表示的意思不尽相同，要注意把握不同引导词所表示的不同时间关系，以及它在具体句子中对应的时态、语态等问题。
注意： as（在??时候，因为）， since （自从，因为），它们可以引导时间从句，并强调主句和从句的动作同事发生。并且 while 有时还可以表示对比。例如：
（ 1）While my mother was reading the newspaper, I was watching TV.（read 是延续性的动
词， read 和 watch 同事发生）
I like playing football while you like playing basketball. 我喜欢踢足球，而你喜欢打篮
球。（对比）
（2） when（当??的时候），引导的从句的谓语动词可以是延续性动词，也可以是瞬间动词。从句动作可与主语动作同事发生，也可在其后发生。
I was reading a book when she came into my room.（come 是瞬间动词，只能用 when 引导，不
能用 while）
I often missed my home when（while） I lived in NewYork. （ live 是延续性动词， when 可用while 代替）
（ 3）when 和 while 的区别还在于： while 引导的时间状语从句多用于进行时态，而 when 引导的时间状语从句多用于一般时态。
While they were talking, the bell rang. 正在他们谈话的时候，上课铃响了。
（ 4）as 译作“一边??一边”、“随着??”，侧重主句和从句的动作同时发生。有时可与when， while 通用。
We always sing as we walk. 我们总是边走边唱。（ as 表示“一边??一边”）
As you grow, you will know more and more 。随着年龄的增长，你会懂得越来越多。
2.till 或 until 引导的时间状语从句
till ， until （直到??才）：一般情况下两者可以互换，但是在强调句型中多用 until 。 till 不可以在句首，而 until 可以放在句首。
注意：如果主句中的的谓语动词是瞬间动词时，必须用否定形式；如果主句中的谓语动词是延续性动词时，用肯定或否定形式都可以，但表达的意思不同。例如：
I didn ' t go to bed until（till） my father came back. 直到我父亲回来我才上床睡觉。（ go to bed 是瞬间动词，主句用否定形式）
I talked until he came back. 我工作到他回来为止
I didn't work until he came back. 他回来我这才开始工作
在我到达之前等我。
Please wait until I arrived.
3.since 引导的时间状语从句
Since （自从）：引导的从句的谓语动词可以是延续性的动词，也可以是瞬时动词。一般情况下，从
句谓语动词用一般过去时，而主句的谓语动作用现在完成时。但在 It is+ 时间 +since 从句的句型中，主句多用一般现在时。例如：
I have been in Beijing since you left. 自从你离开以来，我一直在北京。
Where have you been since I last saw you? 自上次我和你见面以后，你到哪里去了？
It is five months since our boss was in Beijing. 我们老板离开北京有五个月了。
4.由 before 和 after 引导的时间状语从句
注意：（ 1） before （在??之前）：引导的从句不再用否定的谓语。
（ 2）当主句用将来时，从句总是用现在时；如果before 引导的从句谓语用的是过去时。则主句
动词多用过去完成时，这样以便体现动作发生的先后。
（ 3）after （在??之后）：表示主句动作发生在从句动作之后。如果主句用的是过去时，则从句多用过去完成时。例如：
It will be four days before they come back. 他们要过四天才能回来
My father had left for Canada just before the letter arrived. 我父亲恰好在信到之前去
加拿大了。
After we had finished the work, we went home. 完成工作之后，我们回家了（从句用过去完
成时，主句用一般过去时）
5.由 as soon as ,immediately, directly ,instantly, the moment, the instant, the minute, 等引导的时间状语从句：这些连词都表示“一??就”。例如：
I will go there directly I have finished my breakfast. 吃完早饭，我立即到那里去。
The moment I heard the news, I went to the school. 我一听到消息，马上赶到了学校。
As soon as I reach Canada, I will ring you up. 我一到加拿大，就给你来电话。
注意 hardly （ scarcely ， rarely ）?? when,before ，no sooner ?than 相当于 as soon as 之意。主句用过去完成时，从句用一般过去时态。当 hardly ， scarcely, rarely 和 no sooner 位于句首时，主句应用倒装语序。例如：
Hardly had I sat down when he stepped in , 我刚坐下，他就进来了。
二、原因状语从句
原因状语从句表原因，常见的引导词有： because （因为）， since （既然）， as（既然）， for （因为）
1.becausey 引导的原因状语从句一般放于主句之后， because 表示直接原因，语气最强，回答 why 引导的疑问句必须使用 because。
I do it because I like it..
Why didn ' t he come yesterday?
—— Because he had something important to do.
注意“not ?? because ” 结构中的 not 否定的是 because 引导的整个从句，例如： The country is not strong because it is large. 国强不在大 .
2．Since 引导的原因状语从句一般位于主句之前，表示已知的、显然的理由。通常被翻译成“既
然”，较为正式，语气比 because 弱。。
Since you are free today, you had better help me with my mathematics, 既然今天你休息，你最好帮我补习数学。
3.as 引导原因状语从句时表示附带说明的“双方已知的原因”，语气比 since 弱，较正式，位置较灵活，常放于主句之前。
As it is raining, you ' d better take a taxi ，既然在下雨，你最好乘出租汽车。
4. for 引导的原因状语从句并不说明主句行为发生的直接原因，只提供一些辅助性的补充说明， for 引导的原因状语从句只能放于主句之后并且必须用逗号将其与主句隔开。
He could not have seen me, for I was not there. 他不可能见过我，因为我不在那里。
三、条件状语从句引导条件句常用的连词有 if （如果）， unless （如果不，除非）等，条件状语从句和时间状语从句一样，表示将来要用一般现在时态。
We won' t let you in unless you show your pass.
If you fail again this time,what will you do?
（1）if 引导的条件状语从句表示将来时，要用一般现在时代替，主句仍使用一般将来时态。
（ 2）将 if 引导的宾语从句和状语从句进行混淆考查，宾语从句中的if 表示“是否”，可以使
用一般将来时。
四、让步状语从句
让步状语从句表示“虽然，即使，尽管”。引导词有 although ， though ， even though, even if 都表示“虽然，即使，尽管”之意。主句中不能用 but ，但可用 yet 、
Though 和 although 语气较弱（其中的 though 比 although 通俗，不如 although 正式）， even if 和 even though 带有强调意味而显得语气更强。例如：
Although they are poor ,they are happy yet. 虽然他们很穷，但很快乐
The article is very important though it is short. 那篇文章虽然很短，但很重要。
Even though it was raining, she walked to work. 即使下雨，她也是走着去工作的。
I ' ll visit him this evening even if I can stay only a few minutes. 今晚我将去拜访他，即使我只能停留一小会儿。
注意 though 引导的让步状语从句的用法比较特殊，它可以倒装，也可以不倒装。
五、地点状语从句
地点状语从句常由 where 和 wherever 引导，通常可置于主句之前或之后。
如： We should go where （ver ） we are most needed, 我们要去最需要我们的地方。
Where there is a will, there is a way. 有志者，事竟成。
六、目的状语从句
目的状语从句通常由 so that, in order that 引导，所引导的从句通常放在主句后面。目的状
语从句中的谓语常含有 may （might ）,can （could ）,shall ,will 等情态动词。
如： He always takes a seat in the first row so that/in order that he can hear better.
= In order that he can hear better, he always takes a seat in the first row. 为了听得
更清楚，他总是坐前排的座位。
七、结果状语从句
结果状语从句常由 so that, so ? that, such ?that 等引导，放在主句之后， so ? that 与 such ?that 句型在一定条件下可转换。
如： He made such an excellent speech that everyone admired him.
= He made so excellent a speech that everyone admired him. 他的演讲如此精彩以至于每个人都很钦佩他。
注意 so that 引导结果状语从句和目的状语从句的辨别
so that 从句之前有个逗号的常为结果状语从句，因表示某一行为带来的结果，从句中的时态常 为过去式；
so that 从句中有 may （ might ）， can （ could ）， should, will 等情态动词的通常是目的状语从 句。
如： I wrote as clearly as possible, so that I got high
marks.( 这样可以得高分。
He went to the lecture early so that he could get a good
seat. 告了，以便可以找到一个好座位。
He went to the lecture early, so that he got a good seat. 这
样他就找到一个好座位。
八、比较状语从句
1. 比较状语从句常由 as ?as ，not so （ as ）， than 引导。比较从句部分常为省略句。
如： His brother is as handsome as he （is ）/him.（ 非正式英语中可用宾格 him ） 他弟弟和他一
样英俊。
He swims faster than any other student in his class （does ）. 他比班上其他任何人都游得快。
2. 通常把 the more ? the more ?结构也归为比较从句，意为：“越?越”。
如：The harder you work, the greater progress you 'll make. 你越努力学习，就会取得越大
的进步。
The less she worried, the better she worked.
目的 ）我尽可能地写清楚些， （目的）他很早就去听报 结果）他很早就去听报告了，
她担心得越少，就工作得越好。
九、方式状语从句
1. 方式状语从句常由（ just ） as（像?）， as if/though （好像）引导，表示动作的方式。
如： Do exactly as the doctor says. 一定要按照大夫的话去做。
He walked slowly as if/though he had hurt his leg. 他慢慢地走着，仿佛是腿受了伤。
注：在非正式问题中有时会用 like 代替 as 引导方式从句。
2.as if/though 引导的状语从句，若描述非事实情况，常用虚拟语气，若描述的是实际情况，用陈述语气。
如： She treats the orphan as if/though he was her own child. 她对待孤儿就像是她自己的
孩子一样。（他是孤儿，当然就不是她亲生孩子，故用虚拟语气。）
It looks as if/though it 's going to rain. 看起来天像是要下雨了。（本句用的是陈述语气，
说明天真象是要下雨了。）
实战演练（2 ×50）计分 :
1. I don ' t know if it tomorrow ,if it , we won ' t go on a picnic.
A.rains; rains
B.will rain; rains
C.will rain; will rain
2. We can ' t go to the zoo ___ the weather is fine tomorrow.
A.unless
B. if
C. because
3.Just work hard, your dream will come true.
A. but
B. and
C. or
4.Don ' t cross the street the traffic lights are green.
A. after
B. until
C. when
5. _ they may not succeed, they will try their best.
A. Though
B. Because
C. Unless
6.We will have no water to dink we don ' t protect the earth..
A. until
B. before
C. if
7.Luckily, all the students got out of the teaching building if fell down.
A. until
B. before
C. after
8.My grandma didn ' t go sleep I got back home.
A. where
B. until
C. as soon as
9.Uncle Wang gave all his savings to the Hope School he himself was not rich.
A. because
B. as if
C. though
10.You ' ll do better you are more careful with your spelling.
A .if B. before C. although
11.The sports meeting will continue it rains this afternoon.
A. if
B. since
C. unless
12.I ' ll give her the message she comes back.
A. till
B. before
C. as soon as
13. ________________________________ Jim is going to be a doctor when he .
A. will grow up
B. grows up
C. grow up
14.— Did you catch what the teacher said?
—No. She spoke so fast I couldn ' t hear her very clearly.
A .which B. that C. when
15.The teacher speaks very loudly all the students can hear her.
A. so that
B. because
C. since
16.Study hard, ___ you will catch up with your classmates.
A. and
B. or
C. but
17.Several days has passed _____ the terrible earthquake happened in Japan.
A. after
B. since
C. as
18.It ' s raining outside. Don ______________ 't leave it stops.
A. When
B. since
C. until
19. _______ it ' s difficult to make her dream come true, but she never gives up.
A. Though
B. /
C. Because
20. __ you go to the party, you will have a good time.
A. If
B. Though
C. Because
21.--- Is WuDong at school today ?
- No, he is at home _ he has a bad cold.
A. When
B. Though
C. Because
22.There are many books on math in the bookshop that he can ' t decide which to choose.
A. so
B. too
C. such
23.He got up early he could get to school on time
A. even though
B. as if
C. so that
24.She is short she can ' t reach the buttons of the lift
A .so, that B. such, that C. too, to
25.---Mum, what did the doctor say ?
--- He asked me to live the air is fresher.
A. where
B. when
C. because
26.The piano in the other shop will be
,but
A. cheaper ; not as better
B. more cheap; not asbetter
C. cheaper ; not as good
27.All of us haven ' t seen Mike he left our city.
A. when
B. until
C. since
28.they are poor, yet they are very honest.
A. Because
B. Although
C. When
29.---What was the party like?
Wonderful. It ' s years I enjoyed myself so much.
A. after
B. before
C. since
30.W hy do you want a new job you got such a good one already?
A. that
B. where
C. when
31. You will be late you leave immediately.
A. unless
B. until
C. if
32.W e won 't give up we may fail ten times.
A. even if
B. since
C. whether
33.T he new secretary is supposed to report to the manager as soon as she
A. will arrive
B. arrives
C. is arriving
34.T he volleyball match will be put off if it
A. will rain
B. rains
C. rained
35. It rained heavily that they didn ' t come.
A. as
B.too
C. so
36. I often visited Tian ' an Men Square I was staying in Beijing.
A. until
B. during
C. while