1、温馨提示： 此套题为Word版，请按住Ctrl,滑动鼠标滚轴，调节合适的观看比例，答案解析附后。关闭Word文档返回原板块。课堂15分钟达标练Forces other than damaging winds are also at work inside tornadoes. Sometimes, as the wind passes a house, the walls and ceiling burst apart as if a bomb had gone off inside. This explosion(爆炸)is caused by the low air pressure(压力
2、)at the center of a tornado. The pressure at the center of a tornado is usually 13 pounds per square inch. However, inside the house the air pressure is normal, about 15 pounds per square inch. The difference of 2 pounds per square inch between the inside and outside pressure may not seem like much.
3、 But suppose a tornado passes over a small building that measures 20 by 10 by 10 feet. On each square inch of the building, there is 2 pounds of pressure from the inside that is not balanced by air pressure outside the building. On the ceiling, that adds up to an unbalanced pressure of 57, 600 pound
4、s. The pressure of the four walls adds up to 172, 800 pounds. If windows are open in the building, some of the inside air will rush out through them. This will balance the pressure inside and outside the building. But if the windows are shut tightly, the huge inside pressure may cause the building t
5、o burst. Unfortunately, heavy rain often occurs in the storms that later produce tornadoes, so people often shut their windows. This may cause far worse damage later. 【语篇概述】本文主要讲述龙卷风除了具有破坏力极大的风之外, 多种力也作用于其内部。. Skim the passage and tell us the main idea. The passage mainly tells us . 答案：the damage wh
6、en a tornado occurs. Read the passage again and choose the best answers. 1. What did the paragraph before this passage most probably discuss? A. Measuring rainfall from a storm. B. The powerful winds of tornadoes. C. The kinds of damage caused by explosions. D. Repairing the damage from tornadoes. 【
7、解析】选C。推理判断题。文章一开始就谈到龙卷风发生时, 内部的低压引起的“爆炸”会造成墙倒屋塌。在此之前很可能谈论的是“爆炸”所引起的各种破坏程度。2. Which of the following is the main topic of the passage? A. How tornadoes can be prevented. B. When tornadoes usually occur. C. Where tornadoes are formed. D. Why tornadoes cause so much damage. 【解析】选D。主旨大意题。文章主要是围绕龙卷风造成破坏的
8、原因来展开的。3. What is the difference per square inch between the air pressure inside a building and the air pressure inside a tornado? A. 2 pounds. B. 10 pounds. C. 13 pounds. D. 15 pounds. 【解析】选A。数字计算题。根据第二段内容及该段第三句 “The difference of 2 pounds per square inch between the inside and outside pressure may
9、 not seem like much. ”可知建筑物每平方英寸的气压之差是2磅。4. Why do people shut windows when tornadoes occur? A. Because the wind is strong. B. Because there is heavy rain. C. Because the weather is foggy. D. Because the weather is cold. 【解析】选B。细节理解题。根据文章最后一段可知答案。5. Which of the following statements is WRONG? A. The
10、 low air pressure at the center of a tornado causes the explosion. B. The pressure inside of the house is more than that inside a tornado. C. The balance of the pressure inside and outside the building causes the explosion. D. The open windows cant cause the building to burst. 【解析】选C。细节理解题。根据文章倒数第二段
11、可知建筑物内外压力的不平衡导致该建筑物被摧毁, 因此C项错误。. Read the passage carefully and fill in the blanks. Forces other than 1. _winds are also at work inside tornadoes. This explosion is 2. _by the low air pressure at the center of a tornado. The pressure at the center of a tornado is 3. _from that inside the 4. _. There
12、 is 5. _ pounds of pressure from the inside that 6. _ balanced by air pressure outside the building. If the 7. _are shut tightly, the huge inside pressure may 8. _the building to burst. Unfortunately, heavy 9. _often occurs in the storms that later produce 10. _. 答案：1. damaging 2. caused 3. different 4. building 5. 2 6. isnt 7. windows 8. cause 9. rain 10. tornadoes关闭Word文档返回原板块