引导时间状语从句的从属连词(以下称引导词)很多，为方便记忆，现作以下分类：
1. 基本类
包括before, after, when, while, as, since, till, until, once, as soon as 等。如：
Did anyone call when I was out? 我不在家时谁来过电话吗?
We have known each other since we were children. 我们从小认识。
You’ll feel better after you take the pills. 吃完药丸后你会感到好一些。
Make sure that all the lights are off before you go to bed. 睡觉前一定要关灯。
Don’t promise him anything till we’ve had time to think about it. 在我们 有时间考虑之前别答应他什么。
2. 名词类
即由名词词组充当引导词，包括the moment, the minute, the second, the instant 等(均表 示“一……就……”。如
I loved you the instant (that) I saw you. 我一见到你就爱上你了。
Tell me the moment (that) you get the results. 你一拿到结果就给我打电话。
3. 副词类
即由副词充当引导词，如 immediately, directly, instantly等。如：
I came immediately you called. 你一打电话我就来了。
Directly I walked in the door I smelt smoke. 我一进门就闻到烟味。
4. 短语类
主是几个涉及time短语，如every time，each time，(the) next time，any time，the last time，the first time 等。如：
Next time you come in, please close the door. 下次你进来，请关门。
My roof leaks every time it rains. 每次下雨，我的房顶就漏。
He felt nervous each time she spoke to him. 每次她和他讲话，他都感到紧张。
The last time we talked he said he needed another two days. 上次我们谈话时他说他还需 要两天。
5. 句型类
包括no sooner…than, hardly…when 等。如：
I had no sooner closed the door than somebody knocked. 我刚把门关上就有人敲门。
Hardly were the words uttered when he began to regret them. 话刚说出口他就开始后悔了 。
