题目内容：

以 Health and diet 为题,写一篇不少于80个单词的短文.
要以这些为基础：
it is necessary to keep a balanced diet ;
should ;
it is important to do regular exercises ;
it is essential to keep in good spirits / in a positive mood ;
renew our spirits and release our stress ;
Be bound to keep healthy ;
How to Keep Healthy