No one knows for sure when or why it began to symbolize peace.

没有人确切地知道它是什么时候或者为什么开始成为和平的象征。

youdao

It is impossible to predict when or why anyone of us may require help at home.

它是无法预测何时或为何我们任何人都可能需要在家里的帮助。

youdao

Suskind and I argue that we don't know how, when or why the decision was made-though we suspect it was much earlier.

而我和苏斯金德则认为，我们并不知道这个决定是如何做出的，是什么时候做出的，以及为什么要做出这样的决定，尽管我很早之前就对此决定有过怀疑。

youdao

That's why when we officially entered the recession or the challenging situation caused by the financial crisis, I keep asking myself, "What should we do?"

由于金融危机而导致的经济衰退,使得公司处于困境，我一直自问，我们能做些什么？

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Or you can say "Why don't we~?" when you are suggesting that you, as well as others, take a particular action.

当你想建议自己与其他人一起做出某种行动时，你可以说“Why don't we~?”。

Why don't 课堂 - SpeakingMax英语口语达人

Why? How could neurons be all or nothing when sensation is very graded?

为什么,既然感觉是渐增的,那神经元又怎会是服从全或无法则的呢

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There was no information about when or why he returned, and no details about whether he would actively take up the duties of office.

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It's not quite clear when or why we forgot about them, but in Tuscany, where I now live, favas are snatched up as soon as they appear, to be shelled at the table and eaten raw with young pecorino.

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The most perplexing aspect of being a parent is that you can (almost) never discern when or why a child will follow your directives, as opposed to hear what you direct him to do and then do the exact opposite.

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