soon as…一…就…= directly / immediately / instantly…
 = the second / the minute / the moment / the instant…

He came around to see me as soon as / the moment/ immediately he checked in the hotel.
他刚一入住宾馆就来看我.
They informed us the news immediately / directly they got it.
他们一得到消息就通知了我们.
The policeman came to the spot the moment / the instant / the minute she heard of the accident.一听说事故,这位警察就到了现场.

2.…,before….
(1) 没来得及…就…
The roof fell before he had time to dash into the room to save his baby.
他还没有来得及冲进房间把孩子就出来,房顶就塌了.
He ran off before I could stop him.
To my great disappointment , my favorite singer left the concert before I could have a word with him.

(2) 过了多久才怎么样,动作进行到什么程度才怎样
They walked about thirty miles to the west before they saw a village.
They worked day and night about three days before everything returned to normal.
Three years passed before I knew it.

3.It was + 时间段 + before….过了多久才….
It was not long before… 不久就…
It will ( not ) be + 时间段 + before …要过多久 ( 不久)…..才…..
It was not long before he sensed the danger of the position.
It was three years before he came back.
It will be half a year before you graduate from this school.

4. no sooner …than…= hardly…when…一…就…., 刚刚…就…
No sooner / hardly + 过去完成时,than / when + 一般过去时
如果no sooner, hardly 位于句首, 主句要倒装.
He had hardly sat down to have a rest when the door bell rang and in came Allan.
No sooner had he got off the train than his daughter ran towards him.
Hardly had we arrived when she started crying to go home.

5. once 一旦…., 表示时间和条件
Once you understand this rule, you will have no further difficulty.
Once you have decided to do something, you should do it well.
Once you enter the chemistry lab, you should follow the teacher’s instructions.

6. since … 自从….以来
Since 引导的从句不论是延续性或非延续性动词, 都表示的是动作或状态的完成或结束.
注意一下句子翻译:
Since he lived in Nanjing, I have not heard from him. (= since he left Nanjing…)
自从他离开南京以来,我没有收到过他的信.
Since she was in Yangzhou, she has kept in touch with her former friends. ( since she left Yangzhou…)
她离开扬州以来,一直同过去的朋友保持着联系.
对比:
1). I have never seen him since he was ill.
他病好后,我就再也没有见到他.
2). I have never seen him since he fell ill.
他生病以后我就再也没有见过他.
It is / ( has been ) + 时间段 + since + 过去式
It is / has been two years since his father died.
= his father has been dead for two years. = his father died two years ago.
他的父亲去世两年了.
It has been 8 years since I graduated from university.
= I graduated from university 8 years ago.
It is 3 years since he smoked. 他三年不吸烟了.(即,从句动词延续性的,译成否定意义;从句动词非延续性的,译成肯定意义.)
It is 3 years since he left school.-----他毕业三年了.

7.…,until…直到…时候; not…until…直到…才…
You are to stay here until / till your mother comes back.
The meeting was put off until ten o’clock.
Not until we watched the Earth Day program on TV did we know much about global warning.
= We did not know much about global warning until we watched the Earth Day program.
= It was not until we watched the Earth Day program on TV that we knew much about global warming.
Not until he failed in the exam did he realize that he had wasted much time playing computer games.

8. …when…引导并列分句, “当时,突然”,强调另一动作的突然发生.
One day Chuck was on a flight across the Pacific Ocean when suddenly his plane crashed. Chuck survived the crash and landed on a deserted island.
I was walking along the river when I heard a drowning boy crying for help.
I was about to leave when it began to rain.
对比: A: I was walking along the street when I caught sight of a tailor’s shop.
    B: I was walking along the streets. Just at that moment I caught sight of a tailor’s shop.

9. while = although尽管
While I admit that the problem is difficult, I don’t think that it can’t be solved.
While I admit his good points, I can see his shortcomings.
While I was angry with her, I didn’t lose my temper.

10. where 地点状语
You should put the book where it was.
Persistent people begin their success where others end in failure.
Where there is a will, there is a way.
Where men are greedy, there is never peace.
Go where you should, keep on studying.