when
音标发音
- 英式音标 [wɛn]
- 美式音标 [wɛn]
- 英式发音
- 美式发音
基本解释
- adv. 什么时候；什么情况下；什么场合下；（用于时间的表达方式之后）在那时，其时；当时，当场
- pron. 什么时候；何时
- conj. 在……时候；在……之后；在任何……时候；一……就； 考虑到，既然；虽然，然而，可是
- n. 时间，时候；日期；场合
词源解说
- 直接源自古英语的hwenne，意为何时。
用法辨析
- when的基本意思是“什么时候”。可用作疑问副词,用来询问某事曾发生或将要发生的时间,引导特殊疑问句; 还可用作关系副词引导限制性定语从句、非限制性定语从句和表语从句,表示“是…时候的事”。
- when可用作从属连词,引导状语从句,表示时间时作“当…时,在…的时候”解; 表示条件时作“如果,要是”解; 表示对比时作“既然,考虑到”解。当when所引导的从句的主语和主句的主语一致时,常将其主语、系动词或助动词省去,只留实义动词或表语,或者改写为短语。
- when所引导的时间状语从句用一般现在时代替将来时,用现在完成时代替将来完成时。
adv. (副词)
conj. (连词)
英汉例句
- When did you see him last?
你上次是什么时候见到他的? - Often she will weep when alone.
她一个人时常哭。
用作副词 (adv.)
用作连词 (conj.)
词组短语
- Remember When 记得当时;曾几何时;记妥当时
- Say When 酒斟够了请说一声;够了就说;够了就请告诉我
- When Rendering 只有在最后渲染时才重新计算更新效果;渲染时
- When all 此时;当所有
- Use When 何时用;什么时候用
短语
英英字典
- at what time; at the time at which
- what/which time
- (CONSIDERING THAT) considering the fact that
- (ALTHOUGH) despite the fact that
- You use when to ask questions about the time at which things happen.
- If something happens when something else is happening, the two things are happening at the same time.
- You use when to introduce a clause in which you mention something that happens at some point during an activity, event, or situation.
- You use when to introduce a clause where you mention the circumstances under which the event in the main clause happened or will happen.
- You use when after certain words, especially verbs and adjectives, to introduce a clause where you mention the time at which something happens.
- You use when to introduce a clause that specifies or refers to the time at which something happens.
- You use when to introduce the reason for an opinion, comment, or question.
- You use when in order to introduce a fact or comment which makes the other part of the sentence rather surprising or unlikely.
剑桥英英字典
柯林斯英英字典
专业释义
- 既然
- 时间
The simulation results show that the identification rate can achieve 99 % and the average identification time is 1.8 ms,when position noise is in the max position error.
仿真实验表明:当位置噪声在估计最大位置误差范围以内时,本算法识别成功率可达99%以上,平均识别时间为1.8 m s,很好地满足了星图识别的要求。