when like fall use more cut air study so save much how |
Nowadays more and more people care about the exploitation (开采) of the natural resources, such as oil. The oil we use, the less these will be left for the future. Oil can be in many ways and it's difficult to imagine what the modern world will be without oil. But oil isn't easy to find and get out of the earth. Men must the rocks, they think the rocks in a certain place may have oil, a metal tower is built. A machine in the tower a hole down into the ground. At the same time, a steel pipe (钢管) is pushed down to stop the sides from in and to keep out water. At last if the men are right, usually the oil rushes up high into the. If the oil catches a light , there will be a terrible fire, a kind of cover is fixed on the top of the pipe. And the oil can run out through taps( 活塞). Today the price of oil keeps rising all the time. In many countries, the governments encourage people to oil as much as possible.