东北大学《大学英语》课件-第4讲.pdf

Text C PC Pollution More than 12 million get thrown away every year in the US alone.Are we talking about cars?Telephones?No,computers.By 2006,as many as 350 million of them will be obsolete.How many is 350 million?If you counted at the rate of one number per second,it would take 10 years to count that high.And consider this:Computers contain hazardous materials,like mercury,chromium and lead.Just one computer may contain 2.25 kilograms(five pounds)of lead.All that adds up to an enormous amount of toxic waste.Text C The computer industry itself is largely to blame for the problem.More powerful computers are needed to run newer software.Yet the machines often cannot be upgraded easily and become obsolete in just two or three years.Samsung has even made a throwaway computer,which is sealed so that it cannot be upgraded.What do people do with their old,perfectly useable but outdated computers?Most people did not know what to do with them.As a result,many old computers ended up gathering dust in homes and many more were simply thrown out with the trash.Text C Nowadays,some companies are thinking of ways to reduce the amount of computer junk.Sony has agreed to help recycle old Sony products.Dell,Hewlett-Packard and others now take back some equipment.To make computers useable longer,Toshiba is developing a computer with a rewritable cartridge that can be upgraded for minimal cost.Dell and Compaq are trying to design computers with parts that can snap in and out.Simply upgrading parts instead of buying a whole new computer will cut down on waste.Text C Laws are being passed,too.In Europe,computer companies will have to pay for collecting and recycling their discarded products.And 70 percent of computer waste must be recycled.The idea behind the laws is that computer companies themselves should pay the cost,which will encourage them to design equipment that is easier and cheaper to repair and upgrade.Other laws require manufacturers to phase out some metals,including mercury and chromium.Unfortunately,some companies and trade organizations are fighting such laws in the US.Text C Yet while many people are throwing away good computers,others cannot afford them at all.Hundreds of organizations are working to resolve this problem.They collect and repair old computers and some of these agencies also teach computer repair skills as well.The computers then go to schools,charities and needy individuals.Alternatively,they might be put to good use in third world countries.Donating a used computer to one of these organizations can turn one persons trash into someone elses treasure and cut down on waste,too.(446 words)obsolete adj.no longer used;out of date 废弃的；过时的 Will computers make books obsolete in the near future?The introduction of gunpowder gradually made the bow and arrow obsolete,particularly in Western Europe.count v.say or name the numbers in order,one by one or by groups 算；数 As the saying goes,”Dont count your chickens before they are hatched.”I was amazed at the number of plants in the small garden-I counted 147.rate n.a value,cost,speed,etc.,measured by its relation to some other amount 速率；比率 If you are an average reader you can read an average book at the rate of 300 words a minute.The government has made great efforts to control the birth rate in recent years.hazardous adj.(of an activity)which contains risks or danger 危险的；冒险的 Because of the bad weather,driving conditions are expected to be hazardous tonight.Recent surveys reveal that 94 percent people believe smoking is hazardous to health.mercury n.a silvery-white poisonous metallic element,liquid at room temperature 水银，汞 Dont touch that liquid!It is mercury and poisonous.Mercury is liquid at ordinary temperatures,and is often used in thermometers.chromium n.a blue-white metallic element found only in combination with other chemicals 铬 Chromium can be used to harden steel alloys and produce stainless steels.Chromium is often used to cover metal objects with a shiny silver protective surface.kilogram n.the base unit of mass in the International System,equal to 1,000 gram 千克，公斤 The young girl is a little overweight for her age,weighing 55 kilograms.Something weighing one kilogram on the earth would weigh only about 160 grams on the moon.toxic adj.of,related to or caused by poisonous substances 有毒的；中毒的 The poisoning was due to the presence of some toxic materials in the new product.A number of toxic substances that humans encounter regularly may cause serious health risks.largely adv.mainly;for the most part 主要地；大部分地 The chief foods eaten in any country depend largely on what grows best in its climate and soil.A great deal of the knowledge we have about household goods comes largely from the advertisements we read.upgrade v.raise to a higher grade or standard 升级 Youll need to upgrade your hard drive to 4Mb before running this new software.No one has noticed more than the cable industry,which has been slow to upgrade its aging systems.throwaway adj.designed or in