第一篇       Mobile Phones

　　Mobile phones should carry a label if they proved to be a dangerous source of Fadiation．according to Robert Bell，a scientist．And no more mobile phone transmitter towers(发射塔)

　　should be built until the long．term health effects of the electromagnetic radiation they emit(放射)is scientifically evaluated．he said．"Nobody's going to drop dead overnight but we should be asking for more scientitic information．"Robert Bell said at a conference on the health effecfs of low-1evel radiation．"If mobile phones are found to be dangerous．they should carry a warning label until proper shields can be devised．"he said．

　　A report widely circulated(传播)among the public says that up to now scientists do not really know enough to guarantee there are no ill effects on humans from electromagnetic radiation．According to Robert Bell，there are 3.3 million mobile phones in Australia alone and they are increasing by 2，000 a day．By the year 2000 it is estimated that Australia will have 8

　　million mobile phones：nearly one for every two people．

　　As well，there are 2，000 transmitter towers around Australia，many in high density(密度) residential areas．For example,Telstra，Optus and Vodaphone build their towers where it is geographically suitable to them and disregard the need of the community．The electromagnetic radiation emitted from these towers may have already produced some harmful effccts on the health of the residents nearby．

　　Robert Bell suggests that until more research is completed the Govemment should ban construction of phone towers from within a 500 meter radius (半径)of school grounds，child care

　　centers，hospitals，sports playing fields and residential areas with a high percentage of children．He says there is emerging evidence that children absorb low．1evel radiation at a rate more than three times that of adults．He adds that there is also evidence that if cancer sufierers are subjected to electromagnetic waves the growth rate of the disease accelerates(提高)．

　　Robert Bell calls on the major telephone companies to fund adequate research and urges(敦促)the Government to set up a wide ranging inquiry into possible health effects．

　　31 According to Robert Bell，if mobile phones prove to be dangerous to people's health，

　　A they should be banned immediately．

　　B the use of them should be restricted．

　　C all transmitter towers should be torn down．

　　D a warning label should be attached．

　　32 How many mobile phone users will there be in Australia by the year 2000，according to the passage?

　　A  3.3 million．

　　B  Almost half of the population．

　　C  One third of the population．

　　D  One fourth of the population．

　　33 Many transmitter towers were built

　　A  on high mountains．

　　B  in places suitable to the phone users.

　　C  in areas which can take in radiation．

　　D  in densely populated areas．

　　34 Who absorb low-1evel radiation at a higher rate than the others?

　　A  Children．

　　B  Men．

　　C  Women．

　　D  Old people．

　　35 This article mainly argues that

　　A the Goverdnment should restrict the number of mobile phone users.

　　B mobile phones may have ill effects on people.

　　C mobile phones have proved to be harmless to people's health.

　　D no more phone towers should be constructed.

　　第二篇     A Thirsty World

　　The world is not only hungry，it is also thirsty for water．This may seem strange to you，since nearly 75％of the earth's surface is covered with water．But about 97％of this huge amount is sea-water，or salt water．Man can only drink and use the other 3％-the flesh water that comes from rivers，lakes，underground，and other sources． And we cannot even use all of that，because some of it is in the form of icebergs(冰山)and glaciers(冰川)．Even worse，some of it has been polluted．

　　At the moment，this small amount of fresh water is still enough for us．However,our need for water is increasing rapidly．Only if we take steps to deal with this problem now can we avoid a severe worldwide water shortage later on．A limited water supply would have a bad effect on agriculture and industry．

　　In addition to stopping wasting our precious water,one useful step we should take is to develop ways of reusing it．Experiments have already been done in this field，but only on a small scale.

　　Today,in most large cities，water is used only once and it eventually returns to the sea or runs into underground storage tanks．But it is possible to pipe water that has been used to a purifying(净化)plant．There it can be filtered(过滤)and treated with chemicals so that it can be used againjust as if it were flesh from a spring．

　　But even if every large city purified and reused its water,we still would not have enough.Where could we turn next?To the oceans!A11 we'd have to do to make use of the vast amount of

　　sea-water is-remove the salt．This salt-removing process is already m use in many parts of the world．

　　So if we take all these steps，we'll be in no danger of drying up !

　　36 The phrase''the world"in the first line of the passage refers to

　　A  "man"．

　　B  "you"．

　　C  "woman".

　　D  "they"．

　　37 What percentage of the earth's water can man actually use at present?

　　A  Nearly 75 percent．

　　B  About 97 percent．

　　C  Exactly 3 percent．

　　D  Less than 3 percent．

　　38 According to the passage，we can avoid a worldwide water shortage in the furore by

　　A  increasing  rainfall．

　　B  reusing water and utilizing sea-water．

　　C  cutting down our consumption of water．

　　D  reducing the number of factories producing steel．

　　39 Which of the following statements，according to the passage，is NOT true?

　　A  A limited water supply will affect industrial production．

　　B  Every large city purifies and reuses its water．

　　C  Purified water is not exactly as flesh as spring water．

　　D  Oceans are the largest water source．

　　40 According to the passage，sea-water can be tureed into flesh water by

　　A heating it up．

　　B treating it with chemicals．

　　C taking salt out of it．

　　D drying it up．

　　第三篇 Computers in Cars

　　You're far from home on a lonely road.Shadowy forests stretch away on both sides.Athick mist(雾)makes it difficult to see far beyond your car's windshield (挡风玻璃).

　　"Can this be route 90A?"you wonder.If it is ,you should be near a town.Yet there's no hint of one. Night is closing in.And you're low on gasoline.

　　This is a situation where an in -car computer that can navigate would be a big help.

　　A car computer that navigates?Yes!Such computers exist . Several experimental models are being tested by General Motors,Ford,Chrysler,and several foreign car makers.These computers vary in detail. But they all contain series of maps on videodiscs or videotapes.For example,one computer system contains 13,300 maps covering the continental US.

　　Before starting out on a trip,a driver can type in the code for the region he or she plans to drive through.The computer then shows a map of theat region.At the same time,a tiny radio receiver linked to the computer goes to work. It picks up signals from navigation satellites such as the NAVSTAR network.Using these signals,the computer shows the car's position at all times and displays this position on the map.The computer can dalso calculate and display the best route to follow.

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