before long/long before

before long 意为“不久(之后)”( = soon, a little later), long 为名词。

1. We shall finish before long. 我们很快就会干完。

2. Before long she came running behind me. 很快,她就跑着追我了。

3. Before long we got to the station. 很快我们就到了车站。

4. The petrol had nearly all been used up. Before long, the noise dropped completely and the boat began to drift gently across the water. (New Concept English, Book 2, L. 86) 汽油已差不多用完了，不一会儿马达声完全消失，汽艇开始缓慢地漂在水面上。

5. Before long, I leaned over and put my head on her shoulder. It was our first date. (B. Clinton, My Life) 不久,我就俯下身去,把我的头放在了她的肩膀上。这是我们的第一次约会。(《我的生活》)

long before(before 为副词、介词或连词,long 为副词)意为“很久以前”,“早在……之前”。

1. I had known her long before. 很久以前我就认识她。

2. I knew Smith long before I knew you. 早在认识你之前我就认识史密斯了。

3. She died long before the war. 早在战前很久她就去世了。

4. They began the experiment yesterday, but they had made preparations long before. 他们昨天开始做实验，但早在这之前就已经作准备了。