1.(not explained)+ disappearance莫名其妙的；+ object, person神秘的；不可思议的
the police investigation into the mysterious disappearance of a little girl警方针对小女孩的神秘失踪展开的调查
the mysterious celestial objects called black holes称之为黑洞的神秘天体
He began to feel sympathy for this slightly mysterious man.他开始同情这个有些神秘的男人。
The whole thing seems very mysterious.整件事看似十分不可思议。
2.to be mysterious about sth
person +对某事故弄玄虚；对某事态度诡秘
As for his job, he was very mysterious about it.关于他的工作, 他总是故弄玄虚。
3.(not known about)+ illness未知的；奇怪的
A mysterious illness confined him to bed for months.他因一种说不清、道不明的怪病卧床好几个月。
4.(atmospheric)神秘莫测的
The place held the same mysterious allure as had the stones.这个地方与这些石头一样具有神秘的魅力。