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》

I wonder why he has not come back yet.

我想知道为什么他还没有回来。

youdao

One reason why the Internet has not yet started destroying Indian newspapers is that only 7% of Indians surf the web regularly.

互联网尚未开始侵蚀印度纸媒的原因之一是，只有7%的印度人经常上网浏览信息。

youdao

That is one of the major points as to why deafness has not gotten a cure yet.

这就是到目前为止,还没有对策的一个主要原因。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

The Arizona state senator who sponsored SB1070, Russell Pearce, is also Mormon, which has led to speculation that this is why the Mormon Church has not yet expressed a moral opinion on the matter.

ECONOMIST: Utah's immigration debate

Still on a busy day, especially when markets are volatile the settlements office may not find out about the trade until the counterparty calls them days later asking why the deal has not been settled yet.

FORBES: Rouge Trading...Blinded By Profits

It would also explain why the lake required by the original hypothesis has not yet been located.

ECONOMIST: Mass extinctions