朝三暮四

朝三暮四 [zhāo sān mù sì]

1. ■ change one's mind frequently; blow hot and cold; befool others with tricks; become turncoat and change (one's) master(s); capricious; chop and change; contradict one's own words; fickle; keep changing one's mind; play fast and loose; three in the morning and four in the evening; shift and veer:

他这个人朝三暮四， 做起事来总是虎头蛇尾。 He is of a variable mood; he never finishes what he starts.