What's "at all" mean?

Native speaker’s answer
Rebecca
"At all" means "in any way" or "to any extent"! It's used for emphasis. It's usually used with negatives and questions. It works here since it says, "you don't think...?" Ex: I don't know him at all. He's a complete stranger to me. Ex: Do you know how to swim at all? Ex: A: Do you like pizza? B: No, not at all.