catch somebody with their pants/trousers downto discover that someone is doing something that they should not be doing or has not done something that they should have done 〔出其不意地做某事〕使某人猝不及防,令某人突陷窘境 He’s not the first politician to be caught with his pants down, and he won’t be the last. 他不是第一个陷入窘境的政客,也不会是最后一个。
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