听力原文:M: Do you happen to have any stamps in your place? W: Yes, I have some. What stamps do you want? M: Four fifties and tens W: I don't think I have that many. But I have an idea, why not use our school's envelopes? Here you are. M: What is the difference? We still need to buy stamps. W: No, look here, Postage Paid. M: That's great. You are a big help. What stamps does the man want?