资讯
职称外语 新东方在线网络课堂 > 职称外语 > 职称英语卫生类 > 正文

职称英语卫生类A级概括大意模拟题(8)

2017-02-11 12:58:00 来源:新东方在线

  1. Children enjoy shouting at a high wall and hearing the sound come back to them. These sounds are called echoes (回声). Echoes have given us a number of valuable tools.

  2. Echo sounding devices were early used in making maps of the ocean floor. Sounds or ultrasonic (超声的) sounds make good tools for determining how deep the water is under ships. Sometimes echoes from ultrasonic distance finding devices were prevented from working by fish swimming past or by the presence of large objects. So ultrasonic devices have been replaced by other tools. 

  3. Radar is now a familiar tool. Like many others it was an unexpected discovery. It was first observed by two researchers, who were studying sound communication. They were sending signals from a station on one side of a river in Washington,

  D IC. to a vehicle across the river. They discovered that their signals were stopped by passing ships. They recognized the importance of this discovery at once.

  4. All this was of course just a start, from which our present radar has developed. The word "radar," in fact, gets its name from the term "radio detection (检测) and ranging." "Ranging" is the term for detection of the distance between an object and the radar set. Today, in our scientific age, it would be difficult to manage without radar.

  5. One of the many uses of radar is as a speed control device on highways. When a person in an automobile is driving faster than the speed limit, radar will show this clearly and the traffic police can take measures to stop him.

  6. A pilot cannot fly a plane by sight alone. Many conditions such as flying at night and landing in dense fog require the pilot to use radar. Human eyes are not very good at determining speeds of approaching objects, but radar can show the pilot how fast nearby planes are moving.23 Paragraph 2

  24 Paragraph 3

  25 Paragraph 4

  26 Paragraph 5

  A Study of Sound

  B Highway Police

  C Working Principles

  D Early Use of "Radar"

  E Useful Tools

  F Discovery by Chance

  27 Echo-sounding devices were early used to

  28 Ultrasonic device were used to

  29 Police use radar on highways to

  30 Radar helps pilots to

  A detect nearby objects

  B determine the depth of the ocean water

  C decide how fast you drive www.examw.com

  D stop passing ships

  E map the ocean floor

  F observe water flow

  【参考答案】

  23. D 24. F 25. C 26. B 27. E 28. B 29. C 30. A

     本文选自新东方在线论坛。

最新文章

相关文章

四级实用 ? 工具

四六级交流?下载

四级课程排行榜本周本月

四级公开课更多>>

全国大学英语四六级考试听力重大调整解析 w 22分01秒
1 全国大学英语四六级考试听力重大调整解析
视频:新东方在线2015年12月四级考试综合点评 w 24分04秒
2 视频:新东方在线2015年12月四级考试综合点评
视频:新东方在线帅健翔2015年12月四级阅读真题解析 w 25分11秒
3 视频:新东方在线帅健翔2015年12月四级阅读真题解析
视频:2015年12月英语四级写作真题解析 w 22分14秒
4 视频:2015年12月英语四级写作真题解析
2015年12月大学英语四级考试模考卷二 w 28分39秒
5 2015年12月大学英语四级考试模考卷二

推荐阅读