401　it be…before+从句

◎ 这个句型中的before通常不易译为“在……之前”，而常译为“（很久）才……，还没来得及就……，仅……就”等。

It is long before he settled down. 他很久才安顿下来。

It is only two years before they completed the exhibition centre. 他们建成这个展览中心仅用了两年时间。

It was not long before he realized that he'd made a serious mistake. 不久他就意识到自己犯了一个严重错误。

Before I could get in a word she tore the letter into pieces. 不等我说话，她就把信撕得粉碎。

He almost ran into a tree before he saw it. 他差一点儿撞到树时才注意到树。