when
when[hwen; 弱hwən]adv.1.■[疑问副词]2.■什么时候，何时3.■在…情况下4.■从前，以前；当年5.■在…时候6.■[关系副词]彼时，其时conj.1.■什么时候：He told us when to eat.他告诉我们什么时候吃饭。2.■届时，在那时：He came at six, when the sun was setting.他六点钟来的，那时太阳正落山。3.■是…的时候了：He came at a time when we needed help.正在我们需要帮助的时候他来了。4.■当…时，在…的时候：when we are at college当我们还在大学的时候5.■一…就…；当即：The runners started when the gun went off.枪声一响，赛跑运动员就起跑了。6.■每逢，每当：She smiles when you praise her.每当你夸她的时候她就笑。7.■相反，而，却：to complain of one's lot when one might change it本来可以改变自己的命运，却自怨命苦8.■既然； 鉴于：How can he help when they won't let him?既然他们不让他帮，他怎么能去干呢?pron.1.■什么时候n.1.■时间hardly…when…见 hardlySay when.[口语]够时请关照一声。[用于给人斟酒或倒饮料等时]When all is said and done说到底，归根结蒂，毕竟When fortune smiles,embrace her.[谚语]幸运之神来敲门，赶快将她拥抱；好运来时莫错过。When I did well, I heard it never;when I did ill, I heard it ever.[谚语]我干得好时，从没听过赞美；我干得差时，总是听到埋怨。When I die,the world dies with me.[谚语]我殁，世界与我偕殁。When in doubt,leave out.[谚语]新闻不实，宁弃勿用。(报纸编辑的座右铭)
whenwhen[(h)wen]adv.1.■[疑问副词]什么时候, 何时2.■[关系副词]当...时When will he come?他什么时候来?It was a time when motorcars were rare.那是汽车很罕见的时代。I still remember the night when Nanjing was liberated.我还记得南京解放那天晚上的情景。词性变化when[(h)wen]conj.1.■当...时2.■一... 就...3.■如果4.■虽然; 然而; 可是5.■既然6.■考虑到; 那时; 然后It was raining when we started.我们动身时正下着雨。We'll start when the team leader comes.队长一来, 我们就出发。Turn off the switch when anything goes wrong with the machine.如果机器发生故障, 就把电门关上。We have only three books when we need five.虽然我们需要五本书, 却只有三本。Why use wood when you can use plastic?既然能用塑料, 为什么还要用木料?We played outside till sunset, when it began to rain.我们在户外一直玩到太阳下山, 那时天下起雨来了。when[(h)wen]pron.1.■[疑问代词]什么时候2.■[关系代词]那时Since when have you been here?你从何时起就在这个地方的?We came a week ago, since when the weather has been bad.我们一星期前来到这里, 从那时起天气一直不好。when[(h)wen]n.1.■(事件发生的)时间 the when and where of an act 行为发生的时间和地点Tell me the when and the why (=reason) of it.请告诉我时间和原因。
继承用法whenissuedadj.1.■(股票, 证券)虚股的whennessn.1.■时间性[关系]
