When和While的区别.docx

1、 When 和 While 的区别
when,while 都有“当 时候”的意思 .
when 既可表示某一点时间 ,也可以表示某一段时间 .
（一）在 when 引导的时间状语从句中 ,其谓语动词可以是其形式为 : 形容词 /现在分词 /过去分词 /介词短语
/such+be+ 主语。
Happy are those who are contented. 知足者常乐。
Growing all over the mountain are wild flowers. 漫山遍野长满了野花。
Seated on the ground are a group of young people.
Inside the parcel was a letter. 包裹里有封信。

席地而坐的是一群年轻人。
Such were his words.( = Such was what he said.)

这就是他说的话。
二、部分倒装 (Partial Inversion)
把 be 动词、助动词或情态动词置于主语之前的句子叫部分倒装句。
主要有下面几种 :

这类句型
1. Only

修饰的副词、 介词短语 或状语从句置句首时
Only then

did I

begin my work.
Only if you ask many different questions

will you

acquire all the
information.
Only in this way can we learn English well.
只有用这种方法我们才能学好英语。
使用特点 :
在部分倒装句中 , 如果谓语部分无助动词 , 则需找助动词来 “帮助 ”构成倒装句。
(x) Only after the war learned he the sad news.
( √ ) Only after the war did he learn the sad news.
只是在战后他才得知那个不幸的消息。
only 修饰状语从句时 , 从句不可倒装 , 主句倒装。
(x) Only when did he return we found out the truth.
( √ ) Only when he returned did we find out the truth.
只是当他回来的时候 , 我们才查明了真相。
only 修饰主语时 , 句子不可倒装。
(x) Only can he answer the question.
( √Only) he can answer the question. 只有他能回答这个问题。
含有否定意义的词语在句首（否定词有 never,not,not
only,little,seldom,hardly,few,nowhe