The air we breathe , the water we drink are the parts of our environment. We love our planet , but nowadays it has got a lot of ecological problems. Factories poison the plants , the air and the water.People kill animals and destroy their habitats. Not only animals , but also plants ,birds,and insects are in danger.There are a lot of endangered species of fish,reptiles,birds, and mammals in the Earth nowadays , because of people's activity . Many countries protest against dumping industrial wastes into the seas and oceans ,because it pollutes the water ,and kills fish and sea animals . People all over the world pritest against nuclear weapons ,because it can be the cause of the global world catastrophe! We must survive! We must save our beautiful planet!