
Cambiare tono
Cambiare registro / Cambiare musica

Change one's tune 
Sing a different tune / Whistle a different tune / Dance to another tune
Cambiare registro / Cambiare musica

Change one's tune 
Sing a different tune / Whistle a different tune / Dance to another tune
Significato
Cambiare, di solito in meglio, atteggiamento e modi perché obbligati
Esempi
Vedi di cambiare registro e comportarti da persona civile se vuoi continuare a vivere qui. In casa mia si seguono le mie regole!
You'd better change your attitude and behave like a decent person if you want to keep living here. My house, my rules!
Il commesso stava trattando in modo molto villano un cliente che reclamava, ma cambiò subito tono quando si accorse che il proprietario lo stava guardando
The salesman was really mistreating a customer that was complaining a lot until he suddenly changed his tune when he realized that the owner was looking at him
Joe ha sempre fatto il gradasso vantandosi delle sue "malefatte", ma ha cambiato musica dopo essere stato arrestato dalla polizia
Joe used to brag about his illegal behavior, but when the police finally caught him and told him it was serious stuff, he started dancing to another tune