[Gohan was so focused on talking with the turtle and trying to help it meditate, he wasn't even aware of anyone else being around. So when Izuku speaks him, it causes him to jump a little. So much for serenity, huh...]

Huh? Oh... Y-Yeah! If you analyze your opponent's moves, you can look back at what you did wrong, plan a different move, and let the new outcome play out in your head. Then you're prepared for the next time you encounter that!