Hundreds of years ago, life was much harder than it is today. People didn't have any machines.
Life today has new problems. One of the biggest is pollution. Water pollution makes our rivers and lakes dirty. It killed our fish and polluted our drinking water. Noise pollution makes us talk louder and become angry more easily. Air pollution is the most serious kind of pollution. It's bad to all living things in the world. Cars, planes and factories all pollute our air every day.
Many countries are making rules to fight pollution. Factories must now clean their water before they pour it into the river.
We need to do some things, too. We can go to work by bus, on foot or with our friends in the same car. If there are fewer people driving, there will be less pollution.
Rules are not enough. Every person must help to fight pollution.
