1、as soon as 它的意思相当于“A事情发生以后,就做B这件事”.
这个短语用的比较常用,口语和书面语都可以.它的特点是,在句子中的位置比较灵活,而且可以用于各种时态.例如：
I’ll write you as soon as I get there.
我一到那儿就给你来信.（一般现在时）
As soon as I went in, Katherine cried out with pleasure.
我一进门,Katherine 就高兴的叫起来.（一般过去时）
I’ll return the book as soon as I have read it.
我一读完就把书还回去.（现在完成时）
Andrew left as soon as he had drunk his coffee.
Andrew一喝完咖啡就走了.（过去完成时）
2、no sooner…than 它的意思相当于“刚做完A这件事,就做B这件事”.
例如：
He had no sooner returned than he bought a house.
他一回来就买了一套房子.
如果no sooner 位于句首,主句要用倒装结构.例如：
No sooner had he arrived than he went away again.
他刚到就又走了.
No sooner had the game started than it began to rain heavily.
运动会刚开始,天就下起了大雨.
有一点要注意,no sooner…than 一般用来描述做过的事情,它不能用于表示将来的事.