change one's tune

/tʃˈeɪndʒ wˈɒnz tjˈuːn/

/tʃˈeɪndʒ wˈʌnz tˈuːn/

to change one's tune

to change one's opinion or behavior toward something

Examples

1. He soon changed his tune when he saw how angry I was.

2. The question is, will the president change his tune on taxes?

3. He bragged that the test was easy, but when he saw his grade he changed his tune.

4. He was against the idea to start with, but he soon changed his tune when he realized how much money he'd get.