Air pollution is when someone ruins the air. An example of polluting the air is when people drive their cars. Cars pollute the air because of the gasses that come out of the back. The air gets polluted more by old cars because in the olden days they didn't know that the gasses would pollute the air.
Another type of pollution is water pollution. Water pollution happens when people dump/put stuff in water. An example of water pollution is when people throw cans or the things that hold cans in the water. that is harmful because whales and sharks will eat them and possibly die. Another example of water pollution is when people spill oil into the water. This happens on oil rigs because they dump oil in the water that fish drink.
That is why we should watch out for what we do to the water. Next time you drop something in the water think 'is it harmful?'