Terezi thought for a second on how to explain these things to Stern. "I'm speaking Alternian, my native language." She spoke, "I think the reason you humans speak it might have something to do with your species being created by our game. I mean i thought that was why cool kid and his friends could talk to us," she then spoke up again, smilling a toothy grin full of sharp teeth, "I was not aware there were more of you though. We thought humans went extinct except for the kids in our game," she then laughted at the thought.