初中·课本中不会教你的 242　till, until和not...until

242　till, until和not...until

1　till与until 都可以作介词和连词，表示“直到，直到……为止”，在较正式的文字里常用until 。

She was busy from morning till night in those days. 在那些日子里，她从早忙到晚。（介词 ）

Please stay here till I come back. 请在这里等我回来。（连词 ）

They waited for her until dawn. 他们等她一直到天亮。（介词 ）

You can't eat anything until you see the doctor. 看了医生你才能吃东西。（连词 ）

提示

till与until用于肯定句中，谓语动词通常是延续性动词，表示该动作延续到till与until表示的时间为止。

You'd better stay in bed till tomorrow. 你最好躺在床上直到明天。

He lived there until 2008. 他在那里一直住到2008年。

2　not...until 是一种常用句型，意为“不到……不……，只到……，之前……不……”。本结构中，until 前的主句谓语动词如果是非延续性的，如go, leave, start, return, buy等。该谓语只能用否定式；如果主句谓语动词是延续性的，如stay, remain等，该谓语动词可用肯定式或否定式。until 后可跟从句，用肯定式，也可跟短语，作时间状语。

I can't give the box to you until I see Mary. 见到玛丽我才能把那只箱子给你。/见到玛丽前我不能把箱子给你。

People do not know the value of health until they lose it. 人们失去了健康才知道健康的价值。

I didn't wait until she returned. 我没有等到她回来。

He didn't go to bed until he finished his homework. 他做完了家庭作业才睡觉。

The boy won't get up till his mother returns. 这男孩直到母亲回来才会起床。

He will go until six o'clock. （误）

He won't go until six o'clock. （正）要到6点钟他才去 。

3　until 可以放在句首，而till 一般不可放在句首。

Until twelve, he lived in the countryside. 在12岁前，他住在农村。（不可用till ）

Until the last minute of the match he didn't give up. 直到比赛的最后一分钟，他都没有放弃。

4　not until 位于句首时，其后的主句要用倒装结构。

比较

They didn't continue their journey until the rain stopped. 雨停了他们才继续旅程。

Not until the rain stopped did they continue their journey.

Not until a few days ago did I get the book. 直到几天前我才弄到那本书。