Air pollution is the human introduction into the atmosphere of chemicals, particulate matter, or biological materials that cause harm or discomfort to humans or other living organisms, or damages the natural environment. Air pollution causes deaths and respiratory disease. Air pollution is often identified with major stationary sources, but the greatest source of emissions is mobile sources, mainly automobiles. Gases such as carbon dioxide, which contribute to global warming, have recently gained recognition as pollutants by climate scientists, while they also recognize that carbon dioxide is essential for plant life through photosynthesis.
The atmosphere is a complex, dynamic natural gaseous system that is essential to support life on planet Earth. Stratospheric ozone depletion due to air pollution has long been recognized as a threat to human health as well as to the Earth's ecosystems.
Someone said here Lei Feng comes in March and goes in April. I thought they were wrong. This afternoon the students of our class went to the bus stop to help the drivers clean the buses.
As soon as the bus stopped at the station, a group of students got on it. Some cleaned the windows, some swept the floor, and others cleaned the wall inside. We worked hard while talking and laughing. When we found some coins lying on the floor, we picked them up and gave them to the conductors or the drivers.They were very happy and said, "It is very nice of you."
When I got home, it was five o’clock. I felt a little tired, but I was very happy to have done a good deed.
Movieis my favorite that I always watch movies when I am free. Since I like English verymuch, so the English movie is my favorite, too. Among so many films I havewatched, the one I like best is HighSchool Musical. This film tells the stories about two high school juniorsfrom rival cliques – Troy Bolton, captain of the basketball team, and GabriellaMontez, a beautiful and shy transfer student who is a hard working girl. Together,they try out for the lead parts in their high school musical. In this process,a series of stories happen, but in the end, the musical achieves great successand Troy and Gabriella fall in love with each other. It’s totally a happyending. I like this movie because the high school life in that is so col
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