Before you swim, you should _____. （  ）

A．do homework

B．do warm–up exercise

C．wear sports shoes

Ken and his father ______ to the park last weekend. (   )

A．will go

B．went

C．go

Answer the questions.
(1)I want to enter the mountain bike race. What are the rules?
(2)Tell a little child something they mustn't do.

选词填空。
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.