五． how to keep healthy    （健康题材）
as we know, keeping healthy is important to us. but what should we do to keep healthy?
first,we should get up early. we should eat healthy food, drink a lot of water and do more exercise . food can give us energy. doing exercise can make us strong. second,we should change clothes often, wash hands often, keep the air fresh and clean and do house cleaning often to stop germs from getting into our bodies.  you shouldn’t keep long fingernails.  at last, we should go to see a doctor at once if we don’t feel well.