Don't you want to know why they are so successful?

你难道不想知道他们为什么这么成功吗？

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When a petrol station burns down, you don't just want to know who dropped the cigarette; you want to know why all the combustible fumes escaped.

当一座加油站被烧毁，你不仅想知道是谁扔下了烟头，你还想了解所有易燃气体的泄露原因。

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I know you did it—I just want to know why.

我知道这是你干的，我只是想知道为什么。

《牛津词典》

"People can look at things and be curious about them, but if you are an explorer you want to know why and how and maybe develop an experiment to test the hypothesis."

VOA: standard.2010.06.21

And this is the reason why enthalpy was invented and why it's so important. Because we want to know this. So this for a finite change.

这也就是为什么焓要被提出,而且如此重要的原因,因为我们想要知道这些。

麻省理工公开课 - 热力学与动力学课程节选

I don't understand why you'd want to take a pill to fix something that we know little about.

我不明白为什么你会愿意吃药片来治好一些我们甚至都不清楚的毛病。

对付压力的方法 - SpeakingMax英语口语达人

Many parents still want to know why so many fell down while other buildings remained standing.

BBC: China marks Sichuan earthquake anniversary

In parts of Andalusia voters want to know why Socialist officials gave friends special pensions.

ECONOMIST: Spain and immigration

The rate of teens having babies is inching up again, and we want to know why.

NPR: Republicans Reach Out to Latinos in Univision Debate