sail under false colours
披着伪装行事；假装是别人
书面/口语·指责欺骗行为
英文释义
to pretend to be someone or something that one is not
例句
The company sailed under false colours, claiming to be eco-friendly.
典故来源
源自海盗历史，船只挂假国旗欺骗敌人，比喻伪装身份或意图。