A: I saw what you did. B: I didn't do anything. A: Oh yes, you did. B: What are you talking about? A: You know what I'm talking about. B: I don't have any idea. A: You know what you did. B: Maybe I know, but how could you know? A: Because I was watching you. B: Okay, I'm sorry I did it. A: Don't drink milk out of the carton. Use a glass! B: I promise I'll never drink out of the carton again.