One thing holds consistent across the numerous worlds of science fiction and fantasy: everyone speaks the same language. Whether it's Lojban, English, Common, or the High Tongue of the Autumn Empire; there's one language that everyone knows, unless plot demands otherwise.
Do not gather and heap up and store for yourselves treasures on earth, where moth and rust and worm consume and destroy, and where thieves break through and steal. Matthew 6:19 KJV
You realize a group of men is going right to you. The man in front has a hard determined look on his face, the two men behind follow him with some uneasiness. He stops before you, holding the handle of his sword in one hand, and slaps (choose person carefully) with leather gloves he carries in the other hand. "Rhadagald Thinvoice, I challenge You to a duel to dea..." Stopping abruptly, he realizes this is the wrong person.