Time passed quickly and three weeks went by ___ we knew it.

问题描述:

Time passed quickly and three weeks went by ___ we knew it.
A.before B.after C.when.D.till
Which one?Why?

A
时光飞逝,三个礼拜在不知不觉中就过去了(既然不知不觉,当然是before we knew it),而且这种说法经常有的.:)