1. (2020八上·腾冲期末) 根据短文内容，判断正误。

There is one thing. We can't see it. Sometimes we can hear it and even feel (感知) it. Without it, all the living things will die. Can you guess what it is? Yes, it is air.

However, what's the air like today?

In cities, there are too many people and too many cars on the roads. The cars send out (排放) a lot of bad gases. In cities, there are many chemical factories. They send out terrible smoke every day. This kind of smoke is dangerous for our health. Now the air is becoming worse and worse. Every day, we breathe (呼吸) the bad air in and out. This makes us feel sick.

So in order to keep us healthy, we have to go to the countryside to breathe more fresh air. Or we can go up hills to get more fresh air.

1. （1） Sometimes we can hear air when it blows.
3. （2） Some living things don't need air.
5. （3） Many people go to the countryside for their holiday because the air there is

   fresher.

7. （4） Too many chemical factories and cars cause the bad air.
9. （5） The smoke from the chemical factories is good for our health.