听力原文：M: Could you give me something for the pain? I didn't get to sleep until three o'clock this morning. W: Aspirin is the strongest medication I can give you without a prescription. M: That isn't strong enough, and I don't have an appointment with my dentist until next week. W: Who is your dentist? M: Dr. Williams. W: Doesn't he have his office on the corner? M: Yes, he does. W: Are you a regular patient? M: Yes. W: Oh. Then I can call him if you like. Dr. Williams will give me a pain prescription over the phone. M: I'd appreciate that very much. Do you think that he'll still be in his office? W: Sure. It's only four-thirty. He should be there until five. M: Good. W: Too bad you can't get an appointment sooner. M: I know. Dr. Williams is always booked up though. I was lucky to get in as soon as I did. W: In the mean time, be careful not to eat or drink anything too hot or too cold. M: I really don't feel like eating or drinking anything at all. W: Well, I'll give Dr. Williams a call and we'll see what we can do for you. Where did this conversation most likely take place?