英语阅读.(3-1)
题目
英语阅读.(3-1)
The people who lived in Rome 2,000 years ago were already complaining about the noise in their city.They couldn’t sleep,they said,with all that traffic in the streets.For them,noise was merely a disturbance.For us it has become a real danger.We know that the sounds of an average city are loud enough to cause serious damage to the inhabitants’ hearing—in the United States,one person out of twenty has suffered some hearing loss.And all over the world the situation is getting worse all the time,since noise increases with the population.
Noise has also increased enormously in the 20th century with the development of machines.We live surrounded by loud planes,trucks,motorcycles,buses,electric tools,radios,pneumatic drills—that roar day and night up to 90 or 100 decibels.The decibel is the unit used to measure the loudness of sound.A normal conversation reaches 55 decibels,thunder roars at 70 decibels,a jet plane goes to 100 decibels and more,and an ordinary subway train,a
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