Definition
To be caught off guard or unprepared when something unexpected happens.
措手不及
Many employees were caught napping when the company changed its policies.
许多员工在公司改变政策时措手不及。
The opponent team's quick attack caught our defense napping.
对手的快速进攻让我们的防守措手不及。
Many investors were caught napping when the market suddenly crashed.
当市场突然崩盘时，许多投资者措手不及。