题目内容：
共用题干Going on a Diet
A typical person needs about 1,800 calories per day to stay alive. These calories keep your heart___ 1 ___and your lungs breathing. They keep your organs operating___ 2___ and,your brain running. They also keep your body warm. A person___ 3___weight because he or she consumes more calories per day than needed. The only way to lose fat is to ___4 ___the number of calories that you consume per day. This is the basic___5___behind going on a diet.
Unfortunately,diets don't___6___or most people. They do lose weight but then go ___7___the diet and put it back. Building a sensible diet and exercise plan is the key to___8___ consistent weight. You need to figure out how many calories you need in a day and how many you ___9___take in. The next step is to add exercise so that you can ___10___the number of cal-onies you can consume per day.
Exercise charts can show you how many calories different___11___of exercise can burn.
Burning 250 or 500 calories per day can___12___ a big difference. You can ride an exercise bike while you are watching TV or you can ___13___ the stairs instead of the elevator. Find an exer- cise___14___.Exercise can be a lot easier if there is someone to talk to. It's a good idea to wear firm-fitting clothes if you are on a diet.___15___clothing acts as a reminder of what you are trying to accomplish.
6._________
A: work
B: start
C: change
D: balance
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