During the last thirty years, the (1) ________ of the world has increased sharply, so it is the same with the (2) ________. Global warming is an (3) ________ serious problem facing the world today. As we all know that there is atmosphere around the earth, which is mainly (4) ________ of nitrogen and carbon dioxide. More and more carbon dioxide from burning the coal and oil is (5) ________ into the air every year. The carbon dioxide can absorb the heat from the earth. The more carbon dioxide in the air, the more heat it will absorb, and the warmer the earth will be. Since the (6) ________ revolution, coal and fossil oil have been wildly used. However, this kind of energy will (7) ________ plenty of greenhouse gases, such as carbon dioxide, methane, (8) ________ vapor and so on. That’s maybe one of the reasons (9) ________ the earth to be warmer. Ruining the forest is also accelerating the (10) ________ of the global warming.