longbefore与beforelong区别
before long = soon ，表示不久以后。 long before = long time ago 很久以前。有时long before 后面可以跟一个句子，这时候before 是连词，引出一句时间状语，表示“在...... 前很久”的意思。
I hope you will be back before long.
我希望你不久就回来。
I saw that film long before.
我很久以前就看过那部电影了。
He had been a party member long before he came to our school.
他到我们学校来之前早就是一个党员了。