The earth is our home. We must take care of it. This means keeping the land, air and water _______. Pollution is a "dirty" word. To pollute means to make things unclean to use. Pollution comes _______ many ways, we see it, taste it and drink it. Pollution is beginning to threaten our health, our happiness and our life. Through the use of poison, man has _______ the land, killing the animals. By putting dirty water and chemicals _______rivers and lakes, we have polluted our_______ water, killing the fish.

Are we turning the world into a big rubbish dump, or is there any hope that we can' get rid of the pollution? .Luckily, _______ people have been warned of the danger of pollution.

Larger numbers of people are now working hard to get pollution under control.

【1】A.to clean B.clean C.cleaning D.cleaned

【2】A.at B.on C.in D.for

【3】A.dug B.made C.used D.polluted

【4】A.toward B.in C.into D.from

【5】A.to drink B.drink C.drunk D.drinking

【6】A.million B.millions C.million of D.millions of