Without oil the modern world could not exist. Oil is needed for travel, becauseit powers our motor cars, buses, trains, aeroplanes and ships. Oil helpsmachines of all kinds, to run easily. Oil also gives us other substances, such asartificial rubber, artificial materials for clothing, and new materials for makingthings. Yet till a hundred years ago no one used oil for any of these purposes.In fact, no one knew that much oil existed.Men do not make oil; they find it. They look for oil in many ways. They beginby making a map of the land where they are searching. Then they use the map to help them in choosing a site to explore with more care. They start their work by examining the rock from under the surface and come to know whether oil islikely to be underneath the rock.To find out how deeply the oil is buried they need to know how far under thesurface the rock is. If everything seems hopeful the men decide to drill downthrough the rock. In this way they find out whether oil really does lieunderneath it. Often this test – well, as it is called, is far away from any townand there is much work to do before any drilling starts. Houses and roads mustbe built for the people coming to drill the test – well. Then the big derrick thatcarries the drill must be put up. This derrick is a strong framework of steelabout 45 meters high. The drill is raised and lowered from inside the derrick.Drilling for oil often means making a well that goes very deep into the earth.Such deep wells have never been made until modern times. The rate of drillingdepends upon the kind of rock being drilled: it can be as fast as 60 meters anhour. Drilling is usually done on dry land, but we can also drill the rock underlakes or seas by putting the derrick on a special platform above the water.1. How is oil useful to machines?2. How do men go about looking for oil?3. Drilling for oil often means _________4. The rate of drilling depends upon ________5. Drilling is usually done on ________6. To find out how deeply the oil is buried we need to​