1 . Pollution
Pollution happens when the environment is dirtied, by waste, chemicals, and other harmful substances(物质).Pollution is a problem all over the world. But it is especially bad in large cities with a lot of industries and cars.
Wildfires, volcanoes, and industrial chemicals cause some air pollution. But most air pollution comes from burning fossil fuels (矿物燃料)These include coal, oil and natural gas. The burning of fossil fuels may release harmful gases. Air pollution may cause such diseases cancer and asthma. It also leads to polluted rain that can harm living things
Causes of water pollution are easy to see. People dump(倾倒) garbage and dirty water into river, lakes and oceans. Factories or cities sometimes release poisonous chemicals, and other wastes into water. These chemicals may make the groundwater unfit to drink.
Littering, or throwing garbage on the ground, is a form of land pollution. Litter can destroy the habitats of plants and animals. The buildup of dangerous chemicals in the ground is another form of land pollution. The chemicals may come from farms or factories.
Many governments, environmental groups, and ordinary people are working to control pollution. Governments have passed laws to keep people from releasing dangerous chemicals into the environment
A.Farmers use chemical to help crops grow. |
B.This type of pollution may be seen in big cities. |
C.They also can harm fish and other forms of life. |
D.These chemicals can spread to plants and animals. |
E.In addition, air pollution may be a cause of global warming. |
F.There are three main forms of pollution: air, water, and land. |
G.Some companies and people are trying to use fewer fossil fuels. |