1.时间状语从句的省略

As(he was)a young man he worked in a store and later in a post office．(95人教版高一上第50页)

年轻时他开过商店，后来又在邮局干过。

提示：

as引导时间状语从句时，不可以跟done或doing，这也是as与when和while的区别之一。

The plane exploded as it was landing．=The plane exploded when/while landing．

飞机在着陆的时候爆炸了。

×The plane exploded as landing．

While(she was)still a student，she played roles in many plays．(人教大纲版高一上第30页)

她还是个学生的时候，就在很多戏里扮演过角色。

We read them when/while(we are)young;we remember them when/while(we are)old．

年少时我们读它们;年老时回忆起它们。

You can read it once again more slowly，using a dictionary when(it is)necessary．(人教大纲版高三第206页)

你可以慢慢地再读一遍，必要的时候可以查字典。

Whenever(it is)possible，you should come and help．

不管什么时候，只要有可能就来帮忙。

The most important thing to keep in mind when dealing(=when you deal)with an emergency is to stay calm．(人教大纲版高二上第59页)

处理紧急状况时，要记住的最重要一点就是保持冷静。

提示：

在这个句子中，虽然我们找不到与主句相同的主语，但是我们可以认为to keep in mind的逻辑主语是you。

When visiting(=when you visit)the house of Americans or Europeans it is polite to look at their books，paintings and small objects in the living room．(人教大纲版高一上第119页)

当你去拜访美国人或欧洲人的家庭时，看一看他们在客厅里摆放的书籍、绘画作品和小摆设是比较礼貌的。

The first country singers sang while(they are)playing the guitar．(人教大纲版高一上第148页)

早期的乡村音乐歌手一边弹吉他一边唱。

John，don't speak until(you are)spoken to．

约翰，记住:在别人跟你讲话之前不要说话。

Once(he was)conscious，he got himself up from the well．

一苏醒，他就从井里爬了出来。

Once(his work had been)published，his work became famous for the absence of rhyme at the end of each line．(人教大纲版高二上第28页)

他的诗作发表后，因为行尾不押韵而大获其名。

提示：

注意下面两个句子不是状语从句的省略:

Once an important army factory in Beijing，Factory 798 was designed by East German architects and built with Russian help in the early 1950s．(人教大纲版高二上第23页)

798厂原本是一家重要的军工厂，20世纪50年代初由民主德国的建筑师设计，俄国援建的。

此句可以把Once an important army factory in Beijing视为名词词组作句子的状语，也有人将其视为Factory 798的非限制性定语。

当使用“before，after和since+-ing”时，不是状语从句的省略。before，after和since是介词，只有在其跟一个完整的句子时，才是从属连词。(人教大纲版高三第49页)

We traveled through four states and decided to spend the winter before we moved on．

我们穿过了四个州，决定过了冬天再往前走。

After studying English(=After he studied English)，he got a small job at a film studio．(人教大纲版高一上第31页)

学习英语之后，他在一家电影制片厂找了一份小工。

Often，these buildings are pulled down after having stood empty without use for many years．(人教大纲版高二上第23页)

=Often，these buildings are pulled down after they have stood empty without use for many years．

这些空空的大楼往往闲置几年后就会被拆除。

Since my coming to London I have not been well．

=Since I came to London I have not been well．

自我来伦敦以来身体就一直不好。