sing a new tune
{v. phr.}, {informal} To talk or act in the opposite way; contradict something said before.
Charles said that all smokers should be expelled from the team but he sang a different tune after the coach caught him smoking.
Syn.: CHANGE ONE'S TUNE, DANCE TO ANOTHER TUNE. Compare: LAUGH OUT OF THE OTHER SIDE OF ONE'S MOUTH.

[TahlilGaran] English Idioms Dictionary ▲