欲加强难度还请移步《地道美语听力播客（快速版）》 Mom:Hold it right there. Put that candy bar down.
Justin:Mom, I just wanted a snack to tide me over.
Mom:Don't you remember what Dad said about this family's need to improve our level of fitness?
Justin:Only old people have to worry about getting fat.
Mom:It's not just about getting fat.
Justin:But I'm just a kid. I'm in great shape.
Mom:Childhood obesity is a huge problem in this country.
Even if you're not overweight, people your age lead sedentary lives.
Justin:Whatever that means.
Mom:It means that you sit around all day as couch potatoes watching TV and playing videogames.
In my day, kids went outside to ride their bikes, climb trees, and run around.
Justin:I don't have that kind of energy.
You and your brothers are lethargic because you don't get enough exercise.
Justin:But exercise is tiring.
Mom:That's because you're not fit.
You have no stamina or endurance.
Justin:I don't need endurance.
It's Saturday and you boys should be outside getting some fresh air.
Justin:In Los Angeles?
Mom:Are you smart mouthing me, young man?
Get outside or you'll all be helping me clean the house.
Justin:We're out of here!