Now more and more children are becoming very heavy . Maybe there are two main reasons .
First , children have a bad eating habits . They like junk food very much . It`s bad for their health . They like to eat in outside , such like McDonald`s and KFC .
Second , children maybe take less and less exercises . They preferrt watching TV and playing computer games to taking exercises . They should go outside and play sport .
We should do more sports and eat less junk food to keep fit .