Ava was ill. She went to see a doctor. The doctor asked her to 1 her tongue（舌头）, and then he said, “OK. You can put your tongue back now. There's 2 wrong with you, but I'm afraid you have a problem: you never take 3 .”

　　“But, doctor,” Ava said, “I don't think so.”

　　“Don't 4 me what you think,” the doctor said, “I see a lot of people 5 you. None of them get any exercise. They sit in offices all day and in front of the TV in the evening. You must walk quickly for at least 20 minutes a day.”

　　“Doctor, you don't understand.” Ava said, “I take enough exercise every day.”

　　“I don't want to 6 any excuse（借口）,” the doctor said, “You must find time 7 exercise. If you don't, you will get 8 and have health problems.”

　　“But I walk every day,” Ava said.

　　“Oh, yes, and I know what kind of walking that is. You walk 9 meters to the bus stop from your house, from the bus stop to your office, and from your office to your dining-room for lunch and back. That's not a real（真正的）walk. I'm talking about a walk by the lake or in the park for 20 minutes every day.”

　　“Would you please 10 me, doctor?” Ava said, “I'm a postwoman. I walk for nearly（几乎）seven hours every day.”

　　For a moment the doctor was silent（无言的）, then he said, “Can I see your tongue again?”