Said of something that has nothing to do with the topic at hand

We are learning to play bridge and you say you'll be good because you are good at poker. What does that have to do with the price of tea in China? Poker has nothing to do with bridge!

Stiamo imparando a giocare a bridge e tu te ne vieni fuori dicendo che sarai bravo perché giochi bene a poker. Il poker con il bridge c'entra come i cavoli a merenda!

After being interrupted for the nth time by comments which were out of place, Mark finally blew up and shouted: “What does that have to do with the price of eggs today?”

Dopo essere stato interrotto per l'ennesima volta da osservazioni fuori posto, Marco è esploso dicendo: “Ma che cosa c'entra? Quello che stai dicendo c'entra come i cavoli a merenda!”