1. It wasn’t long ______ the police caught the thief.(MET92)
A. before B. since
C. until D. when
解析：答案为A。句意为“不久警察就抓住了小偷”。
2. Someone called me up in the middle of the night, but they hung up ______ I could an?鄄swer the phone. (2000全国)
A. as B. since
C. until D. before
解析：答案为D。根据并列连词but可判断出还没来得及接电话，对方就把电话给挂了。
3. It ______ long before we ______ the result of the experiment.( 02上海春招)
A. will not be;will know
B. is;will know
C. will not be;know
D. is;know
解析：答案为C。句意是“要不了多久我们就会知道试验的结果了。”before译作“要不多久就会……”，再由状语从句要用一般现在时代替一般将来时的用法，可知C项为正确答案。
4. He made a mistake, but then he corrected the situation ______ it got worse. (03.北京)
A. until B. when
C. before D. as
解析：答案为C。句意为“他出了差错，但是随后他就调整了局势，以免其进一步恶化”。
5. It was evening ______ we reached the little town of Winchester. (04天津)
A. that B. until
C. since D. before
解析：答案为D。句意为“到了晚上我们才到达Winchester的那个小城镇”。
6. Scientists say it may be five or six years ______ it is possible to test this medicine on human patients. (04福建)
A. since B. after
C. before D. when
解析：答案为C。句意为“科学家说在五六年之后才有可能在人类患者的身体上实验这种药”。
7. The American Civil War lasted four years ______ the North won in the end. (05广东)
A. after B. before
C. when D. then
解析：答案为B。句意为“美国南北战争持续了四年，北方才最终获得了胜利”。
8. It was some time ______ we realized the truth. (05山东)
A. when B. until
C. since D. before
解析：答案为D。句意为“过了一段时间之后我们才了解了真相”。
9. — Why didn’t you tell him about the meeting?
— He rushed out of the classroom ______ I could say a word. (06四川)
A. before B. until
C. when D. after
解析：答案为A。句意为“没等我说一句话，他就冲出了教室”。
10. — How long do you think it will be ______ china sends a manned spaceship to the moon?
— Perhaps two or three years. (06福建)
A. when B. until
C. that D. before
解析：答案为D。句意为“你认为中国多久才会将人造飞船送到月球?”
从以上高考试题不难看出，before含义颇丰。其基本含义是“在……之前”，但由于英汉表达方式的不同，在翻译before从句时，一定要灵活理解before的意思，根据不同语境，确定其恰当含义。现将before的常见含义归纳如下：
1. 当强调从句的动作较主句动作发生得慢或晚时，before常译为“……(之后)才”。例如：
It was a long time before I got to sleep again.过了好长一段时间我才入睡。
It will be five years before we meet again. 五年后我们才会再见面。
He had almost knocked me down before he saw me. 他几乎把我撞倒才看见我。
2. 当强调从句的动作发生之前，主句的动作已经发生时，before常译为“还没有来得及……就……”。此时，从句动词常与can/could连用。例如：
Before he could move, she heard a great noise, which grew to a terrible roar.她还没有来得及迈步，就听见一声巨响，接着就是可怕的隆隆轰鸣。(人教高一Unit 4)
Before he had time to answer, she shut the door. 没容他回答，她就把门关上了。
He beat me before I could say anything.我还没有来得及说话他就把我打了。
3. 当强调主句动作不容迟缓或耽搁时，before常译为“趁着……”、“免得”。此时，主句多为祈使句，暗含条件之意。例如：
Strike the iron before it is hot.趁热打铁
Go at once before I change my mind.马上走，免得我改变主意。
4. 当强调主句的动作与从句的动作一先一后发生时，before常译为“先……，然后……”。多用于某些习语中。例如：
Look before you leap.三思而后行。
Be a pupil before you become a teacher.先做学生然后做先生。
5. 当主句中含有表示意愿的情态动词will/would时，before常译为“宁愿……决不……”或“与其……毋宁……”。例如：
I’d shoot myself before I apologized to him.我宁死也不向他道歉。
He will die before he gives up.他宁死不屈。
6. 当从句为“before sb. realized/knew it.”时，常将before译为“不知不觉就……”。例如：
Tom fell in love with Mary before he knew it.汤姆不知不觉爱上了玛丽。
Time passed quickly and three months went by before Aqiao knew it.时间飞逝，不知不觉中阿巧度过了三个月。
7. 连词before与barely，scarcely, hardly连用，强调主句与从句的动作一前一后紧接着或几乎同时发生时，常译成“刚……就”。例如：
We had hardly begun to walk before it began to rain. 我们刚一举步就下起雨来了。
She had scarcely entered the room before the phone rang. 她一进屋电话就响了。
8. 译为“(不多久)就”，主句多为否定句，尤其在“It + be + not + 段时间+before……”句式中。例如：
It wasn’t long before he told us about this affair. 没多久他就跟我们讲述了那件事情。
I hadn’t waited long before he came.我没等多久他就来了。
I had not gone a mile before I felt tried. 还没有走一英里路，我就觉得疲倦了。
