No air means death. There is air around us36we can’t see it. Air is everywhere and it gives37　to every living thing. We can’t live38it. Bad air makes people ill. We must have fresh air to keep us39.
In the city there are a lot of people and there are too many40running on the road. The gas which the car sends out is made up of(组成) bad gases. Every day we41it in andout. This makes us feel sick. There are many42, too. From the chimneys(烟囱) of these factories, we43get the smoke in black color. This kind of smoke is44to our health. So in order to keep us healthy, we have to go out to the45to breathe more fresh air. Or we can go up hills to get more fresh air.
小题1:A. because B. though C. so
小题2:A. life B. name　 C. pleasure
小题3:A. with B. without C. below
小题4:A. quiet B. tall　 C. healthy
小题5:A. dogs B. trains　 C. cars
小题6:A. breathe B. draw　 C. bring
小题7:A. animals B. people C. factories
小题8:A. usually　　 B. never　 C. seldom
小题9:A. helpful　　 B. erous C. necessary
小题10:A. office　 B. city C. Countryside