注意：
（1）when, as, while
when即可引导持续性动作，又 可引导短暂性动作。它可以表示主句 的动作和从句的动作同时发生，或从 句的动作发生在主句动作之前。如：
When I was a boy, I used to go to the seashore on Sundays.（同时） When the lesson was over, we began our writing. （从句动作在前）
由that, so that, so…that, such…that引导：
It was very cold, so that the river froze.
The book is so written that it gives a quite wrong idea of the facts. There were so many people (=such a lot of people) in the room that we could not get in. He made such an excellent speech that every one admired him.
while也可做并列连词，表示对照的 意思。如： He is tall while his brother is short. 当when, as, while表示“在…一段 时间里”，主从句的动作同时发生时， 可以换用。如： While (When或As) we were discussing, Mr. Smith came in.
注意：
① 在强调句中强调原因状语从句， 只能用because引导，不可用as或
since，如： It was because he was ill that he didn’t go with us.
② because可以引导表语从句,而
as, since不可以，这时状语一 般都是it, this, that
While：指的是“在某一时间里”， “在… 期间”，从句里的动作必须
是
持续性的，它也强调主句和 从句动作的同时发生，往往
如： While he was in London, he studied music. While we were watching TV, he was writing a composition.
He treats me as if I were his own son.
He walked as if he were drunk.
8、比较状语从句：
由连词as…as, not so(as) …as, than等引导： I hope it was as good as the one you lent me. Actually the ocean floor are almost as irregular as the exposed land area.
(3) by the time, each time, every time, immediately, the moment, the instant, the minute, soon after, shortly after都可以作为连词，引导 时间状语。如：
By the time he was fourteen, he had taught himself advanced mathematics.
※目的状语从句中谓语动词常含有may (might), can (could) should, will等情 态动词。 lest (以免，免得), for fear that I hid the book lest (=for fear that) he should see it.
5、结果状语从句：
6、条件状语从句: 由 if, unless, as long as (=so long as) (只要), in case (that) (如果，万 一)等引导： If plastics and rubber are burned, they give off poisonous gases.
Unless you work hard, you will fail, You can go out, as long as (so long as ) you promise to be back before eleven.
Each time he came, he would call on me. You must show him in immediately he comes. I recognized him the moment I saw him.
(4) till和until ①如果主句谓语动词是持续动词， 通常用肯定式的主句，表示“直到… 为止”。如： I worked till (until) he came back.
He heard a noise, as if someone was breathing. I saw the man looking about him as if he wished to impress upon his mind everything.
as if和as though意义和用法大致一 样，引导的从句多用虚拟语气，但也 可用陈述语气。
1、时间状语从句： 引导时间状语从句的从属连词 有：when, while, as, whenever, before, after, since, till, until, as soon as, once…等引导。如：
When he was still a young man, he was forced to leave his homeland for political reasons.
In case I forget, please remind me about that. 注意：条件状语从句中的谓语动 词的时态不可用将来时，只能用现在 时态或过去时态表示将来时。
7、方式状语从句：
由连词：as, as if, as though引导：
The teacher told the students to do as he did. Leave it as it is.
3、原因状语从句： 通常由连词：because, as, since, now that引导。区别是: because：表示“因为”，直接而明确的 原
因和理由，语气最强，why提
问的句子，一般都用because 回答。 He didn’t co语气比because 弱。 you are here, you must do it. Since as：表示“因为”语气比because轻， 引 导从句可放主句前也可放主句后。 You needn’t go with me, as you are busy. As I was afraid, I hid myself.
2、地点状语从句： 通常由连词where和wherever引导。如： Go back where you came from. Wherever you go, you must write to your parents. Where there is a will, there is a way. Where there is too much, the poison and waste may do great harm to the things around us.
② 如果主句谓语动词是瞬间动词，
则用否定式的主句表示“直 到… 才”。如： I didn’t go to bed until (till) he
came back.
③放在句首表示强调时一般用
until。如：
Until he returns, nothing can
be done.
（5）时间状语从句中谓语动词 不能用任何一种将来时， 只能用现在时和过去时表 示将来时。
as引导持续性动作，侧重主句和从 句的动作同时发生。
He hurried home, looking behind as he went.
I saw your sister as she was getting on the bus yesterday. He sang as he walked.
now that意思与since相似，表示“既 然”。 Now that you are in High School, you will probably spend more in reading. Now that all the guests have arrived, let’s have our dinner.
It’s because he is too lazy.
③ for也表示“因为”，但是并 列 连词，它连接的不是状语从
句，语气比较强。 It must be morning,for the birds are singing.
4、目的状语从句： 通常由that, so that, in order that, so…that, lest, in case（以防、免得）等 引导： He got up early in order that he could catch the early bus. She married him so that she might tend and comfort him. I explained again and again in case he should misunderstand me.
2003年名师课堂辅导讲座—高中部分
状语从句
大连市第八中学 孙君 高级教师
1、本讲内容：学习状语从句。
2、学习要求：
（1）掌握状语从句的种类。
（2）学会引导状语从句的从属连词。
3、学习指导： （1）本讲重点：状语从句的种类。