阳一套，阴一套yáng yī tào , yīn yī tào

act one way in public and another in private; be a double-dealer; carry fire in one hand and water in the other;double-faced; have a variety of tricks in one’s dual tactics; run with the hare and hunt with the hounds;wear one face in public and another in private
❍ 我也觉察到，那个人～，很难打交道。I also noticed that fellow carried fire in one hand and water in the other and it was hard to have dealings with him.