引导词：when, as, while, as soon as, while, before, after, since,
till, until, the minute, the moment, the second, every time, the day，
the instant, immediately , directly, no sooner … than, hardly …when,
scarcely … when
I didn't realize how special my father was until I was 18.
While Tom was watching TV, his wife was reading.
No sooner had I arrived home than it began to rain.
Every time I take your advice, I get into trouble.
引导词：where, wherever, anywhere, everywhere
Generally, air will be heavily polluted where there are factories.
Wherever you go, you should bring the mp3 player with you.
引导词：because, since, as, since, seeing that, now that, in that,
considering that, given that, considering that, inasmuch as,
Now that everybody has come, let's begin our clas.
Considering that he is no more than 10 years old, his height of
1.60 m is not normal.
引导词：so that, in order that, lest, in case, for fear that，
in the hope that, for the purpose that, to the end that
The boss asked his secretary to give him the letter so that he could
send it out himself.
The instructor raised his voice that the students at the back could
hear more clearly.
引导词：so … that, so… that, such … that, such that, to the
degree that, to the extent that, to such a degree that,
He got up so early that he caught the first train.
It's such a good chance that we must not miss it.
引导词：if, unless, as/so long as, only if, providing/provided that,
suppose that, in case that, on condition that
We'll start our project if the manager agrees.
You will certainly succeed so long as you keep on trying.
Provided that there is no opposition, we shall call off the meeting.
引导词：though, although, even if, even though, as(用在让步状语从句中
必须要倒装)，while ( 一般用在句首 )，no matter …， in spite of the
fact that, while, whatever, whoever, wherever, whenever, however,
Much as I respect him, I can't agree to his proposal.
he old man always enjoys swimming even though it is cold.
No matter how hard he tried, she could not change her mind.
引导词：as(同级比较), than(不同程度的比较), 特殊引导词：the more …
the more … ; just as …， so…; A is to B what /as X is to Y;
no … more than; not A so much as B
She is as bad-tempered as her mother.
The house is three times as big as ours.
The more you exercise, the healthier you will be.
Food is to men what oil is to machine. 食物之于人，犹如油之于机器。
引导词：as, as if, how, the way
When in Rome, do as the Roman do.
She behaved as if she were the boss.
Sometimes we teach our children the way our parents have taught us.
主要有when, while, as, by the time, before, after, since, till/until,
as soon as等。其中when?while和as都可表示"当……时候",但用法有区别:
When I got home, he was having supper.
They sang as they danced.
While I was sleeping, my father came in.
原因状语从句一般由because, since, as, for引导. 注意as, because, since
1) 如果原因是构成句子的最主要部分, 一般用because。because引导的从句一
I missed the train because I got up late.
2) 如果原因已为人们所知, 或不如句子的其余部分重要, 就用as或since、since
As he was not well,I decided to go there without him.
Since this method doesn't work, let's try another.
I decided to stop and have lunch, for I was feeling quite hungry.
1) so...that结构在某种情况下可以与enough to和too...to结构相互转换。例如:
She is so short that she can't reach the buttons of the lift.
=She is too short to reach the buttons of the lift.
They missed the bus so that they were late for class.
so that也可引导目的状语从句, 此时可用to或in order to替换, 将其改为简单句。
He got up early so that he could get to school on time.
=He got up early to get to school on time.
=In order to get to school on time,he got up early