when的多种意思（高中英语语法）

Posted 2023-03-09

一、作为副词,它有以下的用法:
1. 作为疑问副词,引导特殊疑问句,意为“什么时候;何时”。
如: ( 1 ) When will they come back?
( 2 ) What time will they come back?
回答 when 引导的从句,不一定指出具体的时间点。如回答句( 1 )可用 tomorrow, next month 等。而回答 what time 引导的问句,则必须说出具全的时间点,如 at two o'clock, at five past ten 等。
2. 作连接副词,引导名词性从句或不定式,意为“什么时候”。从句使用陈述句语序,时态根据实际情况而定。
如: ( 1 ) I'd like to know when they will come. 我想知道他们什么时候来。( when 引导宾语从句)
( 2 ) Can you tell me when the bank opens? 你能告诉我银行什么时候开门吗?( when 引导宾语从句)
( 3 ) When she'll be back depends much on the weather. 她何时回来在很大程度上取决于天气。( when 引导主语从句)
( 4 ) Have you decided when to go sightseeing? 你们已经决定什么时候去郊游了吗?( when 引导不定式结构)
3. 作疑问代词,常和介词 since, till, up to 等连用,意为“什么时候”。
如: ( 1 ) Since when have they had the house? 他们从什么时候起有这幢房子的?
( 2 ) Till when is the library open? 图书馆开放到几点呢?
4. 作关系副词,引导限制性定语从句和非限制性定语从句。
如: ( 1 ) The days are gone forever when the Chinese people were looked down upon. 中国人民被人轻视的日子一去不复返了。
( 2 ) The main school holidays are from mid-December till early February, when the days are long and warm. 学校的主要假期是从 12 月中旬到 2 月初,这段时间里白天长而且很温暖。
( 3 ) Considering (the time) when these paintings were done, they are in excellent condition. 考虑到这些油画的创作时期,它们保存的状况是极好的。
( 4 ) Do you remember (the time) when the three of us went on a picnic? 你还记得我们三个人去野餐的那段时光吗?
5. 在定语从句中, that 在某些条件下可用来代替 when ,这时其先行词通常是 time, day, moment, year 等。
如: ( 1 ) His mother died on the evening that he was born. 他母亲死于他出生的那晚。
( 2 ) I stay at home on the days that I am not busy. 在我不忙的时候,我就呆在家里。
6. 在某些含有“时间”的名词词组后面,由于该名词不表示时间,或整个名词词组已用作连词,所以不用 when 引导。如: the moment, the instant, the minute, the second 等等,意为“一……就……”,引导时间状语从句。
如: ( 1 ) The first time I went to China, I visited Beijing. 我第一次来中国就游览了北京。
( 2 ) I thought her nice and honest the first time I met her. 我第一次见到她时就认为她很诚实。
( 3 ) The instant I saw him I knew he was my brother. 我一看到他就知道他是我兄弟。

二、作为从属连词,引导状语从句,表示多种语法意义:
1. 表示时间,意为“当……时;在……的时候”。
A. 在时间、条件等状语从句里,用一般现在时表示将来时;当需要表达将来完成的意义时,必须使用现在完成时来代替。
如: ( 1 ) When you see him, please say hello to him. 见到他时,代我问他好。
( 2 ) When you have finished your experiment, please tidy the lab and put everything back in the cupboards. 当你们做完实验后,请把实验室整理好并把物品放回柜子中。
B. 表示过去发生的事情,在 when 引导的时间状语从句的主从复合句中,动作发生在先的用过去完成时,在后的用过去时。
如: ( 1 ) When I was in Japan, I bought some beautiful pearls. 我在日本时,买了一些漂亮的珍珠。
( 2 ) When I reached the station, the train had left. 当我到达火车站时,火车已经开走了。
2. 表示前面的叙述所没有提到过的信息。它总是对所描述的事件予以引人注目的强调,意为“这时;突然”;当位于句末的分句具有引种用法时,大致有以下三种情况:
A. when 分句前面的分句使用过去进行时。
如: ( 1 ) He was still smiling when the door opened and his wife came in. 他正笑着的时候,门突然开了,他妻子走了进来。
( 2 ) I was thinking of this when I heard my name called. 我正想着这件事时,突然听到有人叫我的名字。
B. when 分句前面的分句使用 was (were) about to, was (were) on the point 等。
如: ( 1 ) We were about to start when it began to rain. 我们刚要出发就开始下雨了。
( 2 ) He was on the point of leaving when someone knocked at the door. 他刚要走就有人敲门。
C. when 分句之前的分句用过去完成时,其中 sb had hardly / scarcely /barely … when 已成为固定词组。如:
( 1 ) We had hardly fallen asleep when the bell rang. 我们刚刚入睡,铃声就响了起来。
( 2 ) He had scarcely arrived when he had to leave again. 他刚刚到达就又要离开了。
3. 表示条件,相当于 if ,引导条件状语从句。
如: How can I get a job when I can't even read or write? 如果我连读和写都不会,我怎么能找到工作呢?
4. 表示对比,主要有以下两种情况:
A. 相当于 whereas, while, since, 意为“既然;然而”。
如: ( 1 ) How can I help them to understand when they won't listen to me? 既然他们不愿听我的,我又怎么能帮助他们弄明白呢?
( 2 ) They have only three copies when we need five. 他们只有三本,而我们却需要五本。
B. when 从句中使用虚拟语气,意为“本来……却……”。
如: ( 1 ) She paid when she could have entered free. 本来可以免费入场,而她却付了款。
( 2 ) She stopped trying when she might have succeeded next time. 她本来下次有可能获得成功,但她却不再尝试了。
( 3 ) They were gossiping, when they should have been working. 他们本该工作,却在那里说别人的闲话。
5. 由 when 等引导的状语从句,如果主语与主句的主语一致或是 it ,谓语动词又含 be 动词时,主语和 be 动词常常被省略,就变成“ when + V-ing/ V-ed/ adj/ 介词词组”的结构。
如: ( 1 ) When in Rome, do as Romans do. 入乡随俗。
( 2 ) When (we are ) young, we are full of hope. 年轻时,我们大家总是充满希望。
( 3 ) Don't reach sideways when standing on a ladder. 站在梯子上时,不要侧着身子去够东西 参考技术A when 英音：[hwen] 美音：[hwɛn]
副词 ad.

1.(用作疑问副词)什么时候,何时
I'd like to know when they'll let him out.
我想知道他们什么时候放他。
When did you last see Margaret?
你上一次见到玛格丽特是什么时候?
2.(用作关系副词,引导关系从句)当...时
There were times when I didn't know what to do.
有些时候我不知道该怎么办才好。

连接词 conj.

1.当...时
John got engaged to her when travelling last winter.
去年冬天旅行时,约翰与她订了婚。
Don't get excited when you talk.
你说话时别激动。
2.既然,考虑到
How can he get the promotion when his boss dislikes him?
既然上司不喜欢他,那他怎么会获得提升呢?
3.虽然,然而
I had only fifteen dollars on me when the book I wanted cost twenty.
我身上只带了十五元钱,可是我想买的那本书定价二十元。
4.在那时,然后

代词 pron.

1.什么时候,那时
Since when has she taught here?
她从什么时候开始在这儿教书的?

名词 n.

1.(事件发生的)时间[the S]
以上结果由"Dr.eye译典通字典"提供本回答被提问者采纳 参考技术B conj. 既然；当…时；考虑到
adv. 什么时候，何时
pron. 那时；什么时侯
n. 时间 参考技术C 语法问题上258en