| pollute million use but we keep another healthy danger of other with |
The earth is our home; we must take care of it. This means that it is necessary and important ________the land, air and water clean. However, pollution is beginning to threaten(威胁) our
__________, happiness and our life ——we see it, smell it taste it and discuss it.
Men began to________the earth a long time ago. When land was
________up or water became dirty, men had to move to
________places. At first, there weren’t so many people then and there were less trash. All the dirty things could be absorbed (吸收)by nature.
______now this is no longer true. The increase of population and the development
________ industry have changed that. Men are still polluting the environment.
later, ________of people have realized the
________of pollution. A lot of people are now working hard to protec
________ environment. Everyone should try their best to make our environment better and better.