The army has not yet proffered an explanation of how and why the accident happened.

军队还没有提供对该事故如何发生以及为什么发生的解释。

《柯林斯英汉双解大词典》

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First of all, it seems that a successful scientist is full of curiosity—he wants to find out how and why the universe works.

首先，一个成功的科学家似乎都充满了好奇心——他想知道宇宙是如何运作的以及为什么会这样。

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She developed the theory explaining how and why the ozone hole happens over Antarctica.

VOA: special.2009.03.13

It has traditional stories and legends, some quite fanciful, Whose goal it is to explain how and why something is what it is.

它讲述了一些传统故事，有一些还极具想象力，它们试图解释事物的形成方式及成因。

耶鲁公开课 - 旧约导论课程节选

Dakota And this is one of them from 2002 called Dakota, and I think you will see immediately how and why it is related to On the Road.

而这个作品是其中2002的系列之一叫做，我想你们能很快地明白,这个作品和《在路上》有什么样的关联。

耶鲁公开课 - 1945年后的美国小说课程节选

Next step: look to whom we are choosing to interact with, how and why.

FORBES: Why Your Unhappy Personal Life Is Good For Your Career

As the company understands how and why IT is helping the business two things will happen.

FORBES: Eight Steps For Addressing the IT Management Crisis

Exactly how and why things have gone so wrong is a matter of debate.

ECONOMIST: The world's biggest carmaker is at sea and floundering