before的用法

Before的用法

一、用作介词

⒈)指时间上早于，在……之前，如：

We finished the work before noon. 中午以前我们完成了工作.

⒉)指位置在前面，如：

We knelt down before Grandma's grave. 我们在奶奶的墓前跪下。

⒊)指顺序或排列在之前，如：

Your name comes before mine on the list. 名单上你的名字在我之前。

⒋)在某人面前，如：

She said it before the witness. 他是当着证人的面说的。

二、用作连词

其基本含义是“在……之前”，又可以根据不同语境灵活翻译成“才”、“还没来得及就……”、“趁……”、“就”等。具体用法如下：

⒈)与情态动词can/could连用

这时候从句虽为肯定形式，根据汉语表达习惯译成“还没来得及就”，如：

Before I could get in a word，he had measured me. 我还没来得及插话他就为我量好了尺寸。Before she could move, she heard a loud noise, which grew to a terrible roar.

她还没来得及迈步，就听见一声巨响，接着就是可怕的隆隆轰鸣。

→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救孩子，房顶就塌了。

⒉)用于肯定句中强调主句所表达的时间，距离长，或花费的精力大，译成“才”

We had sailed four days and four nights before we saw lands. 我们航行了四天四夜才看到陆地。

We waited a long time before the train arrived. 我们等了很长时间火车才到。

⒊)用于否定句中，强调主句所表达的时间，距离短，或花费的精力小，译成“不到……就”如：

We hadn't run a mile before he felt tired. 我们跑了还不到一英里他就累了。

⒋)主句含有scarcely等半否定副词时可以译为“刚……就”，这时候主句应用过去完成时态，从句用过去时，还可以用when替代before如：

We had scarcely reached the school before/when the bell rang. 我们刚到学校铃声就响了。

⒌)有时还有“宁愿”的意思

I'd shoot myself before I apologized to him. 我宁死也不向他道歉。

⒍)用于It+ be/takes+时间段+before句型

在这一句型中又可以根据主从句的时态分成两种情况。

若主句是一般将来时态，从句是一般现在时。若主句是肯定句意思是“要过多长时间才”；若主句是否定形式则翻译成“用不了多久就”。

It will be two weeks before everything returns to normal. 两周之后一切才能恢复正常。

It will be many years before the situation improves. 这种状况或许要过许多年才能得以改善。It won't be long before we meet again. 用不了多久我们就会再见面的。

这时若主句是一般过去时，从句也是一般过去时。若主句是肯定句翻译成“过了多久才……”或“动作进行到什么程度才……”，若主句是否定形式翻译成“没过多久就”。如：

It was some time before I realized the truth. 过了很长一段时间我才了解到真相。

It wasn't long before she became a brave solider. 没过多久她就成了一名勇敢的战士。

They (had) walked about fifty miles to the west before they saw a village. 他们西行50英里才看到一个村庄。

The workers worked day and night about three days before everything returned to normal.

工人们连续工作3天才使一切恢复正常。

He almost knocked me down before he knew it. 他几乎撞到我了才意识到。

Five years went by before I knew it. 不知不觉，五年过去了。

注意：当主句的谓语动词为延续性动词时，before与until有时可以互换。It was an hour before/until the police arrived.

[高考题回放]

1. It was evening ______ we reached the little town of Winchester.（2004天津）

A. that

B. until

C. since

D. before

2. Scientists say it may be five or six years ______ it is possible to test this medicine on human patients.（2004福建）

A. since

B. after

C. before

D. when

3. Someone called me up in the middle of the night, but they hung up ______ I could answer the phone.（NMET2000）

A. as

B. since

C. until

D. before

4. He made a mistake, but then he corrected the situation ______ it got worse.（2003北京）

A. until

B. when

C. before

D. as

5. It was some time _____ we realized the truth.（2005山东）

A. when

B. until

C. since

D. before

6. The American Civil War lasted four years _____ the North won in the end.（2005广东）

A. after

B. before

C. when

D. then

7. –Why didn’t you tell him about the meeting?

–He rushed out of the room _____ I could say a word.（2006四川）

A. before

B. until

C. when

D. after

8. –How long do you think it will be______ China sends a manned spaceship to the moon?

–Perhaps two or three years.（2006福建）

A. when

B. until

C. that

D. before

It was + 时间段+before….“过了多久才（怎么样）……”

It was not long befor e….“不久，就……”

It will (not) be +时间段+before…“要过多久（不久）……才……”(before从句谓语动词要用一般时态) It not long before he (sense) the danger of the position.

不久他就意识到他处境的危险。

It was five days before he (come) back. 五天后他才回来。

It (be)half a year before you graduate from the school. 再过半年你才能毕业。

It (be)long before they understand each other. 他们大概不久就会互相了解。