大学英语四级新型考试预测试卷.doc

大学英语四级新题型考试预测试卷 Part I Writing 30 minutes 注意：此部分试题在答题卡1上。 Part 1I Reading Comprehension Skimming and Scanning 15 minutes Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions on Answer Sheet 1. For questions 1 - 7, mark Y for YES if the statement agrees with the information given in the passage; N for NO if the statement contradicts the information given in the passage; NG for NOT GIVEN if the information is not given in the passage. For questions 8 - 10, complete the sentences with the information given in the passage. Diamonds are just carbon in its most concentrated form, the element that makes up 18 percent of the weight of your body. There is no other gemstone as cherished as the diamond, but in truth, diamonds are no rarer than many other precious gems. They continue to demand higher market prices because the majority of the diamond market is controlled by a single entity. The Origin of Diamonds Carbon is one of the most common elements in the world, and is one of the four essentials for the existence of life. Humans are more than 18-percent carbon. When occurring in nature, carbon exists in three basic forms, of which diamond is an extremely hard, clear crystal. Diamonds form about 161 km below the Earth’s surface, in the molten rock of the Earth’s mantle, which provides the fight amounts of pressure and heat to transform carbon into a diamond. In order for a diamond to be created, carbon must be placed under at least 435,113 pounds per square inch psi of pressure at a temperature of at least 400 Celsius. If conditions drop below either of these two points, graphite will be created. At depths of 150 km or more, pressure builds to about 725,189 psi and heat can exceed 1,200 C. Kimberlite Pipes Most diamonds that we see today were formed millions if not billions of years ago. Powerful magma eruptions brought the diamonds to the surface, creating kimberlite pipes. Kimberlite is name