(2) Can you remember Klong Saensaeb? People used to enjoy swimming there when it was clean. Some people also used the water for their daily needs. Nowadays, this canal is shallow and dirty. Pollution, such as detergents and waste water has destroyed it. Nobody swims in Klong Saensaeb any more, (3) Air pollution is another great danger. The air in big cities has been polluted by smoke from factories and exhaust fumes from cars and trucks. The chemicals in polluted air enter our bodies every time we take a breath. They slowly poison us and may cause illnesses such as lung cancer. (4) Besides air and water pollution. the loss of trees is another serious problem. The floods in southern Thailand in 1988 were the result of too much logging. People cut down too many trees and did not replace them. When the rain came, there were not enough trees to hold down the soil. The ground could not absorb the water. The sudden rush of water flowed into villages where it swept people and animals aweys