The rain caught them unawares (without warning).

他们意外地被雨淋着（没有警告）。

You caught us unawares by coming so early.

你就来，真没想到。

Her sudden refusal took me unawares.

突然拒绝，出我的意料。

Old age creeps upon one unawares.

不知不觉老年就来临。

She probably dropped the parcel unawares.

可能无意中丢失那包裹。