1.different (adj):khác

2.about (pre):về chủ đề

3.complaint (n):sự than phiền

4.lots (noun plural):nhiều

5.overcrowded adj):đông nghịt

6.power (n):khả năng/sức mạnh

7.too (adv):cũng

8.our (adj):của chúng ta

9.keep (v):gìn giữ

10.connection (n):sự kết nối/mối quan hệ

About two hundred years ago, man lived in greater harmony with his environment because industry was not much developed. Today the situation is quite diffierent. People all over the world are worried about what is happening to the environment because of modern industry and the need for more and more energy. Newspapers and magazines write about water pollution, air pollution and land pollution. Why is there  so much discussion about pollution ? After all, people have been polluting the world around them for thousands of years But in the past, there were not many people and of room in the world so they could move to another place when their settlements became dirty. Now, however, many parts of the world are  people live in big cities and much of our waste, especially waste from factories, electric stations, the chemical industry and heavy industry is very dangerous. Fish die in the lakes, rivers and seas; forest trees die . Much of this dangerous waste goes into the air and is carried by the wind for great distances. The earth is home . We must take care of it for ourselves and for the next generations. This means our environment clean. The importance of this task is pointed out by ecologists, the scientists who study the between living things and the environment. However, each of us must do everything possible to keep the land, air and water clean.