Air pollution(污染) is a big problem. It's bad for all 1 things on Earth，and it is not the only one kind of 2.Water pollution makes fishand pollutes our drinking water. Noise pollution makes us get3more easily.

Many countries are making rules(规定) to fight against pollution. They try to stop people 4 burning coal(煤)in the city and releasing(排放) dirty smoke into the5.And if people use 6fewer cars，the air will get 7.

    8earth is our home. We must protect it and not destroy it. That is to say, we should keep the land, water and air 9.At the same time, we had better plant more trees10they can provide a lot of things for us and make our earth beautiful.

***在建国初说：“现在我们能造什么？能造桌子椅子，……能种粮食，……还能造纸，但是，一辆汽车、一架飞机都不能造”。针对这一现实，1953年党提出以“一化三改”为核心的过渡时期总路线，其中“一化”是指

一个正整数n与它的倒数$\frac{1}{n}$、相反数n相比较，正确的是 (     )