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》

A few years ago, the Army noticed that some soldiers fared better than others, and it wondered: Why?

几年前，陆军发现一些士兵过得比其他人好，这是为什么呢？

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The purpose of this article is to explain why the most effective vision for the future Army will be one that refocuses on the close fight as the centerpiece of land warfare.

本文的目的在于解释这样一个看法，即为何对于未来陆军最具眼光的观点就是近距离作战将做为陆战的核心内容重新成为焦点。

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The reason why the Army ended up in charge of strategic defenses (to use Cold War military parlance) was mainly bureaucratic.

FORBES: Missile Defense Becomes A Navy Mission

That was why the Army sent a hundred soldiers to attack the house where he had lived, more or less openly, for many years.

NEWYORKER: The Kingpins

There are any number of reasons why an army of bankers, bureaucrats, consultants and analysts failed to foresee the strength of the ground-level resistance to the Gresik sale.

CNN: 'THE PEOPLE'S ASPIRATION'