Physical Exercise

Physical Exercise
【正确答案】：Everyone hopes to live happily in the world. Physical exercise is indispensable to a happy life. There is a famous saying: "Life lies on exercise." Although you will not necessarily die without regular physical exercises, they'll certainly help you live longer and more healthily.
Firstly, exercise is good for us to build our bodies. It helps to keep the diseases far away from us.
Secondly, exercise can also train us to response agilely.
Thirdly, exercise can help improve our mood and make our life colorful.
In a word, exercise is helpful, important and absolutely necessary.