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 excuses,” 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 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 seven hours every day.” For a moment the doctor was silent, then he said, “ Can I see your tongue again? ”