Stop. Listen! What do you hear? You may hear many different sounds. Some of those sounds may be noise. Noise is a loud or unwanted sound.
Noise can be caused by many kinds of machines, such as motorcycles, jet planes, farm tractors(拖拉机), rock music is also noise.
What happens to people who live near noisy machines or use them over a period of time? Doctors have found that these people have trouble in sleeping. But, most important, constant(不断的) loud noise can cause a loss of hearing.
Scientists use a unit of measure called decibel(分贝) to measure the loudness of a sound. The sound of a quiet room, for example, measures 35 decibels. Talking measures between 40 and 65 decibels. Sounds from traffic and from some rock bands can measure over 120 decibels. Noise at this high level(层次) causes the great hearing loss.
根据短文内容，选择正确的答案（每小题1分，共5分）
【小题1】According to the passage, noise is .A．any kind of soundB．a loud or unwanted soundC．all sounds that you can hearD．terrible sound【小题2】A decibel is a .A．unit that measures soundB．kind of noiseC．machine that makes loud noiseD．person who hates sound【小题3】According to the passage, loud noise can .A．help people to sleep betterB．stop machinesC．cause a loss of hearingD．kill people【小题4】We can conclude（推断） from the passage that .A．noise is a serious problemB．rock music isn’t noisyC．noise is only from trafficD．some people hate any sound【小题5】Study that diagram below. would be the quietest.
Room Noise Level
A 40~65 decibels
B 35 decibels
C 120 decibels
D 130 decibels
A. Room A B. Room B C. Room C D. Room D B
网友回答
(答案→)B
解析：本文主要介绍了什么是噪音，产生噪音的环境以及噪音对人的危害，以引起我们的重视。
【小题1】根据Noise is a loud or unwanted sound.可知选B。
【小题2】根据Scientists use a unit of measure called decibel(分贝) to measure the loudness of a sound.可知选A。测量声音的一个单位。
【小题3】根据Noise at this high level(层次) causes the great hearing loss.可知选C。
【小题4】通过短文的描述我们可以知道生活中可以产生噪音的环境很多，对人的危害也很大，故是一个严重的问题，选A。
【小题5】decibels是表示音量大小的一个单位，数值越小则声音越小，故选B。