1. 时间状语从句

　　When ---当……时候, 通常指某一特定的时间点，主句与从句的动作同时发生。

　　When I opened the window, I saw him come up.

　　When --- 正在……的时候，突然…。通常主句是进行时或 be about to 时，在翻译的时候，when 可以译成没想到或突然。

　　I was walking along the street , when I met him.

　　When 当从句是进行时，主句是一般时，往往表示不满。

　　Someone knocked at the door when I was having breakfast.

　　When=after

　　When the children had gone to bed, she began to prepare her lessons.

　　While ---在……期间，往往指一段时间。

　　While we were inAmerica, we saw him twice.

　　While ---表示一种不满情绪，意思是这边在干某种重要的事，而另一边在享受等。

　　We are cleaning the classroom while they are playing the football.

　　As --- 一边……一边, 随着

　　She was doing her homework as she was listening to the music.

　　As --- 当……时，指一个动作紧接着一个动作发生，从句通常用进行时。

　　As I was going out, it began to rain.

　　The moment --- 一……就…… =as soon as , immediately,

　　---Did you remember to give Mary the money you owed her?

　　---Yes, I gave her the moment I saw her.

　　Not… until --- 直到……才

　　He didn’t leave the office until he finished the work.

　　Before --- 在……之前

　　The passengers should arrive at the airport an hour before the flight departs.

　　After ---在…… 之后

　　The customer left the ticket counter after he had a quarrel with the ticket agent.

　　Since ---自从……, 通常主句用现在完成时

　　I have never been there again since I graduated from the university.

　　It is just a week since we arrived here.

　　As soon as --- 一……就……

　　Jack went to school as soon as he got well.

　　No sooner than --- 一……就……

　　no sooner… than… 用于句首要求倒装

　　Hardly …when…

　　Scarcely …when…

　　No sooner had he arrived than he went away again.

　　Once --- 一但……就……

　　Once you see him, you will never forget him.

　　Every time, each time 每次whenever 每当

　　Each time he came to town, he would visit our school.

　　2. 条件状语从句

　　引导状语从句的连接词有：

　　If如果, unless除非, as long as只要, As (so) far as --- 据……所知，in case万一, provided that假如, on condition that若是，以…为条件

　　If ---如果

　　If you don’t hurry up, you will miss the plane.

　　Unless --- 如果不, 除非=if not

　　We can’t get there on time unless we book the earliest flight

　　As long as --- 只要

　　We will succeed as long as we keep on trying.

　　As (so) far as --- 据……所知

　　As far as I know, he speaks English very well.

　　In case --- 假使, 如果

　　The plane cannot take off in case it rains.

　　Provided that 如果,有时省略 that

　　The plane will be in good condition provided that it is taken care of carefully.

　　On condition that --- 条件是…

　　He said that he would come to the meeting on condition that no one asked him to speak.

　　注:主从句的动作发生在将来时，则主句用将来时, 从句用一般现在时。

　　If he arrives tomorrow, I will be waiting for him at the airport.