Her uncontrollable coughing was a mystery.

她无法控制的咳嗽是一个谜。

youdao

Their motives remain a mystery.

他们的动机仍然是个谜。

《牛津词典》

He's a bit of a mystery.

他这个人有点儿神秘。

《牛津词典》

He says the methane discovery presents scientists with a mystery because it is still not clear how the gas is being produced.

VOA: special.2009.12.30

If so, then from an evolutionary standpoint any kindness towards an animal that an animal shows towards another animal--is a mystery.

如果这样，从进化论观点看,任何对动物善意行为,一个动物对另一个动物，是个谜团。

耶鲁公开课 - 心理学导论课程节选

And you might think that the existence of these feelings is a mystery from an evolutionary point of view.

你们可能会认为,这些情感,是无法用进化的观点来解释的。

耶鲁公开课 - 心理学导论课程节选

They seemed to hold a mystery as inscrutable as the clotted branches of their mangroves.

BBC: The end of a wandering way of life?

Whether they managed to do it without triggering some huge tax bills remains a mystery.

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Still, as his story conceded, much of the workings of the trusts remained a mystery.

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