catch someone with their pants down
US /kætʃ ˈsʌm.wʌn wɪð ðer pænts daʊn/
UK /kætʃ ˈsʌm.wʌn wɪð ðer pænts daʊn/

1.
抓個措手不及, 發現某人做錯事或尷尬事
to discover someone doing something wrong or embarrassing, or to find them unprepared for something
:
•
The boss caught him with his pants down when he was playing games on his computer during work hours.
老闆在他工作時間玩電腦遊戲時,抓了他個措手不及。
•
The sudden inspection caught many employees with their pants down, as they hadn't prepared their reports.
突如其來的檢查讓許多員工措手不及,因為他們沒有準備好報告。