unaware

The mountain climbers were unaware that a massive storm was approaching from the north.

(Chinese) 登山者们没有察觉到一场大风暴正从北方逼近。

She walked into the surprise party totally unaware that forty guests were hiding in the living room.

(Chinese) 她走进惊喜派对时，完全没意识到有四十位客人正躲在客厅里。