school   cars   easy   air    exercise    use 

    Many people in the world ride bicycles every day. There are more bicycles than in the world today. A lot of Chinese people ride bicycles to go to work or . Bicycles are much cheaper than cars. And it is for people to learn to ride. Bicycles are also used for . It helps us to keep fit. If each family has a car, it will a lot of energy and pollute the . So let us ride bicycle.