long before很久以前,过去时
before long不久之后,将来时
意思一说就明白啦~要是记不住的话~就想“long before”=“long long ago”都是long开头的~我就是这样记住的~
句子：
1
He will come before long.
他不久之后会到.
2
Long before,there was a big museum.很久以前,这里有一座大博物馆.long before
很早以前
before long
adv.
不久以后
before long(=soon)与long before的区别：before long“不久”、“很快”,用于各种时态.例：We'll meet again before long.long before是“很久以前”,单独使用,一般用在过去完成时的句子里.例：They said they had seen the film long before.同时,long before后可以接从句.I had seen the film long before you saw it.
before long; long before辨识
before long相当于soon,a little later,意为"不久或不久以后",常与将来时、过去时态连用,在句中作状语.如：
The book will be published before long.那本书不久将要出版.
Before long he came to Canada to go on with his education.不久以后他去了加拿大继续深造.
long before相当于long,long ago意为"很久；很久以前",常用于过去时或过去完成时.如：
Long before,there is a big museum here.很久以前,这里有一座大博物馆.
I had heard of him long before I came here.我来这儿很久以前就听说过他的情况.