First, we have to reduce to use = using things that contain = contains chemical composition
such as a shampoo or detergent et cetera. = shampoo, detergent, etcetera.
because, using  = It's because using / Using lots of chemical composition is main  = the main cause of earth = the earth pollution.

Second, people need to take public  = the public transportation as much as possible. because, when  = When we take  = drive a car, car = the car is emitting much carbon in the air.
Carbon is also main  = the main cause of earth pollution.
so we have to reduce to take  = driving our own cars.

i think third is the most important method of prevent earth pollution.
it is we dont have to thoughtlessly throw away garbage anywhere =  Finally, I think the most important method in preventing pollution is that we should not thoughtlessly throw away garbage anywhere.
If everyone dont  = will not throw away garbage on the street, I am sure earth  = the earth will be clean.
So / Therefore we have to strive for preventing  = preventing the earth pollution.

i felt over searching the data, = I think / In my opinion, it doesnt need lots of efforts for preventing = in preventing the earth pollution.
So i thought i would try to practice it first.