听力原文：W: Good morning, Dr. Smith. I'm not sure whether you can help me or not, but I'm getting desperate! M: Oh, what's wrong? What is making you so desperate? W: Well, everybody laughs at me because I'm so fat. I've always been overweight. I'm trying to eat less but I don't seem to be able to lose any weight. I don't know what I can do. Maybe you can give me some medication? M: Well, it is not a good idea to eat less. You should eat more healthy food like fruits and vegetables, and avoid fast food like hamburgers and hot dogs. W: But hamburgers and hot dogs are my favorite. M: That's the problem. They contain high calories that cause fatness. In addition to avoiding these high-calorie foods, you should do some exercises. Physical exercise does a lot of good to health and will be an effective way to reduce weight. Medicine is not always the best solution to your problem. W: I know, but I don't have time to do exercise. You know, I'm busy at my work from morning to night. Besides, I am not rich enough to go to the gym. M: You needn't spend much time on exercise and you don't have to go to the gym. I suggest that you walk more regularly. You could get off the bus one stop early and walk the last bit. When you walk, try to walk a little more quickly. You could also use the stairs instead of the elevator. W: That's really a good idea. M: You will succeed if you act in accordance with my suggestions. Questions 23 to 25 are based on the conversation you have just heard. 23. Why does the woman feel desperate? 24. What docs the man advise the woman not to do? 25. What are the two speakers talking about? (20)