while的具体用法

while的具体用法
while的具体用法

while的具体用法
【while的用法】
(1)引导时间状语从句,从句中的谓语动词应用延续性动词或表示状态的词.
eg.While the discussion was still going on,George came in.
当讨论还在进行时,乔治走了进来.
Strike while the iron is hot.
趁热打铁.
★注意:while,when,as表“当……的时候”的区别
while强调同时性或某时间段内一种情况发生时另一种情况出现,与延续性动词连用;when可与延续或非延续性动词连用,在强调“当时”,“这时”之意时when;as强调同时性,指“一边……一边……”一件事情发生,另一件事情立刻发生.
eg.———I’m going to the post office.
———______you’re there,can you get me some stamps?
A.As B.While
C.Because D.If
解析:从该题的题意可以看出C、D两选项不合题意；而as侧重同时性,不合题意;while可指一时间段发生某情况时,另一情况出现,正合题意.
(2)引导让步状语从句,多用于句首.意为“尽管,虽然”.
eg.While I admit his good points I can see his bad.
尽管我承认他的长处,但我也看到了他的不足.
While he loves his students,he is very strict with them.
虽然他爱他的学生,可是他对他们很严格.
(3)While作并列连词用,意思为“而,然而”,表前后意义上的对比或转折.
eg.There’s plenty of rain in the southeast,while there's little in the northeast.
东南部雨量充足,而西北部则很少下雨.
Some people waste food while others haven't enough.
有些人浪费粮食,然而有些人却吃不饱.
eg．She thought I was talking about her daughter,_______,in fact,I was talking about my daughter.
A.whomB.where
C.whichD.while
解析:句意为“她认为我在谈她女儿,而实际上我在谈我的女儿.”whom,which和where分别是引导定语从句的关系代词和关系副词,后一句并非修饰定语从句,故应排除A、B和C选项.
★注意:while与but的区别
二者都有“而,然而”之意,但while强调二者的对比,而but强调前后的转折关系.
(4)引导条件状语,意思是“只要”
eg.While there is a will,there is away.有志者事竟成.
We can surely overcome these difficulties while we are closely united.
只要我们紧密地团结一致,一定能克服这些困难.
(5)while从句中的省略.当while从句中的主语与主句的主语一致,且含有be的某种形式时,从句中的主语连同be可同时省略.
eg.While listening to the radio,she fell asleep.
她在听收音机时睡着了.
While in London,he studied music and painting.
在伦敦时,他学习音乐和绘画.
(6)while可用作名词,意为“一会儿;一段时间”
作名词用时,主要用于短语中:afterawhile“过了一会儿”;allthewhile“一直,始终”;ashort/littlewhileago“刚才”;onceinawhile“偶尔、间或”;wait/rest(for)awhile“等/休息一会儿”.
I haven’t seen her for along while.
我好久没有看见她了.
He usually goes to work by bike,but once in a while he goes by bus.
他通常骑自行车上班,但偶尔也乘公共汽车.