根据材料回答下列各题： Going on a Diet A typical person needs about l，800 calories per day to stay alive．These calories keep your heart___________ (51)and your lungs breathing．They keep your organs operating___________ (52)and，your brain runnin9．They also keep your body warm．A person___________ (53)weight because he or she consumes more calories per day than needed．The only way to lose fat is to ___________ (54)the number of calories that you consume per day．This is the basic___________ (55)behind going on a diet． Unfortunately，diets don’t___________ (56)for most people．They do lose weight but then go___________ (57)the diet and put it back．Building a sensible diet and exercise plan is the key to___________ (58) consistent weight．You need to figure out how many calories you need in a day and how many you___________ (59)take in．The next step is to add exercise so that you can___________ (60)the number of calories you can consume per day． Exercise charts can show you how many calories different ___________ (61)of exercise can burn． Burning 250 or 500 calories per day can___________ (62)a big difference．You can ride an exercise bike while you are watching TV or you can ___________ (63)the stairs instead of the elevator．Find an exercise___________ (64)．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．___________ (65)clothing acts as a reminder of what you are trying to accomplish． ___________