搞懂状语从句的核心在于记住引导各类状语从句的连词。在9种状语从句中，尤以引导时间状语从句的连词数量最多，又牵扯到时态的问题，所以用法最复杂。最常见的10个连词如下图：

　　1类一…就…：

　　除了我们最熟悉的as soon as外，以下10个词或句式同样可以表“一…就…”。

　　其中，1once（一旦）+ 3“ly” （立即，立刻）+4the+n（在那一分那一秒那一刻）的用法与as soon as（和…一样快）相同。注意理解这些词的本义是如何引申出“一…就…”的。

　　例句：我一到家的（时候）天就开始下雨。

　　It began to rain as soon as I arrived home.

　　=It began to rain immediately/instantly/ directly I arrived home.（我一到家立刻开始下）

　　=It began to rain the minute/second/moment/instant I arrived home.（在我到家那一刻开始下）

　　2倒装的用法参考前文英语部分倒装的15种用法=1只有+2也不+3虚拟+4如此+5否定

　　=Hardly had I arrived home when it began to rain.

　　=No sooner had I arrived home than it began to rain.

　　2组相反：

　　since与until(till)相反，before与after相反，并且这4个连词都可以作介词。注意下方例句，连词+句子，而介词+名词性成分。

　　It is/has been 10 years since he moved here/since 2009

　　He didn't go to bed until his mother told him a story/until 11 p.m.

　　He gave away all his money before he died=before his death.

　　He became a teacher after he graduated=after his graduation

　　3个当…时：

　　when和while关于动作延续性的用法相信大家都很熟了。我们来看更难的用法。

　　1.when：正在这时……，这时突然……

　　I was reading a novel when the teacher came in.

　　2. while：然而，位于句中表对比。