In today’s world, almost everyone knows that air pollution and water pollution are harmful to people’s health. However, not all know that noise is also a kind of pollution, and that is harmful to human, too.
People who work and live under noisy conditions usually become deaf(耳聋的). Today, however, scientists believe that 10% of workers in Britain are deafened by the noise where they work. Many of the workers who print newspapers and books, and who weave cloth become deaf. Quite a few people living near airports also become deaf. Recently it was discovered that many teenagers in America could hear no better than 65-year-old people, for these young people like to listen to “pop” music and most of “pop” music is a kind of noise. Besides, noise produced by jet plane or machines will make people’s life difficult and unpleasant, or even make people ill or even drive them mad. It is said that a continuous noise of over 85 decibels（分贝） can cause deafness.
Nowadays the governments in many countries have made laws to reduce or control noise and make it less than 85 decibels. In China, the people’s government is trying to solve not only air and water pollution problems but also the noise pollution problems.
小题1:In the world today, not every person knows .
A．water pollution
B．air pollution
C．harmful pollution
D．noise pollution小题2:Today scientists believe that .
A．90% of all the workers in Britain are not suffering from noise
B．10% of all the workers in Britain are working in noisy places
C．10% of all the workers in Britain are deafened by the noise where they work.
D．90% of all the workers are free from any noise小题3:Those who usually have poorer hearing.
A．weave cloth
B．sell newspapers
C．like listening to music
D．often travel by plane小题4:According to the passage, a continuous noise can make you deaf.
A．in working places
B．of less then 85 decibels
C．of over 85 decibels
D．of only 85 decibels
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