before long与long before■before long 不久，很快。如：I’ll be back before long. 不久我就回来。Before long he got married. 不久他就结婚了。■long before(1) 老早，早就(单独使用，表示比过去某时早得多的时间)。如：She had left long before. 她老早就离开了。That had happened long before. 那事老早就发生了。注：long ago 表示“很久以前”，指的是从现在算起的很久以前，通常与一般过去时连用：I met him long ago. 我很久以前就认识他了。(2) 在……的很久以前，在还没有……的很久以前。如：She had left long before his return [he returned]. 在他回来的很久以前她就走了。He had worked in the factory long before he got married. 在他还没有结婚的很久以前他就在这家工厂工作了。注：此时的主句谓语通常用过去完成时，但有时也可用一般过去时(因为 before 已体现了动作的先后关系)。如：This happened long before you were born. 这事在你还没出生以前很久就发生了。■It is [was, will be] long before……在……前需要很久。如：It was long before he came back. 过了好久他才回来。It won’t be long before we see each other. 不久我们又会见面的。比较：It wasn’t long before he realized his mistake. / Before long he realized his mistake. 不久他意识到了自己的错误。 说明:引用此文请注明出处,并请保留该文章链接地址,谢谢~~