dialogue: M: Everyone seems to be on a diet nowadays. Have you noticed that? W: Everyone seems to talk about that, especially girls. M: A friend of mine was on a sweet potato diet. He ate a sweet potato for breakfast, a sweet potato for lunch and another one for supper. W: That's bad for his health. Has he lost any weight? M: Yes. But he didn't last long. One day he felt sick and was sent to hospital. The doctor had to keep him there for a week. W: I'm very sorry to hear that. I think if you want to lose weight, you should not eat too much but you have to eat all kinds of food, vegetables, fruits etc.. And you should also do more exercise. M: I agree with you.
question: What is the best way to keep diet?
choice: To eat every kind of food. To eat less meat. To eat less and exercise more.
answer: To eat less and exercise more.