Drained. And you don't know why.

而你不知道这是为什么。

youdao

And you don't know why.

而你却不知道是什么原因。

youdao

Now they're yelling at you and you don't know why.

搞不懂为什么他冲你大叫大喊。

youdao

Some of you are probably going to be doctors and you don't know why I'm going to do special relativity or quantum mechanics, but you don't know when it will come in handy.

你们中的有些人可能会成为医生,但你们现在不能理解,我为什么要讲相对论和量子力学,但是说不定什么时候,你就用上了呢

耶鲁公开课 - 基础物理课程节选

And it makes you want to go get that insurance. I don't know why, but it does.

这让你想去买这家保险。我不知道为什么，但这就是这样。

广告泛滥 - SpeakingMax英语口语达人

And if you remember this phrase, I don't know why you would, but this will help you learn the lanthanides in order.

如果你能记得这句话的话，我不管你们是怎么做到的，但是这个确实会帮助你按顺序记住镧系元素。

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You'll never know why you get a job and why you don't.

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