老太婆的嘴唇

老太婆的嘴唇 -- 上下两张皮

比喻：指说的和做的不一致，信口开河，说话不负责任。
谚语：“人嘴两张皮”

YOUR TALK TALKS AND YOUR WALK TALKS,

BUT YOUR WALK TALKS LOUDER THAN YOUR TALK TALKS. 

John C.Maxwell