Scatteredthroughtheseasoftheworldarebillionsoftonsofsmallplantsandanimalscalledplankton.Mostoftheseplantsandanimalsaretoosmallforthehumaneyetosee.Theydriftaboutlazilywiththecurrents,providingabasicfoodformanylargeranimals.Planktonhasbeendescribedastheequivalentofthegrassesthatgrowonthedrylandcontinents,andthecomparisonisanappropriateone.Inpotentialfoodvaluehowever,planktonfaroutweighsthatofthelandgrasses.Onescientisthasestimatedthatwhilegrassesoftheworldproduceabout49billiontonsofvaluablecarbohydrateseachyear.Thesea’splanktongeneratesmorethantwiceasmuch.

Despiteitsenormousfoodpotential,littleeffortwasmadeuntilrecentlytofarmplanktonaswefarmgrassesonland.Nowmarinescientistshaveatlastbeguntostudythispossibility,especiallyasthesea’sresourcesloomevenmoreimportantasameansoffeedinganexpandingworldpopulation.

Nooneyethasseriouslysuggestedthat“planktonburgers”maysoonbecomepopulararoundtheworld.Asapossiblefarmedsupplementaryfoodsource,however,planktonisgainingconsiderableinterestamongmarinescientists.

Onetypeofplanktonthatseemstohavegreatharvestpossibilitiesisatinyshrimplikecreaturecalledkrill.Growingtotwoorthreeincheslong,krillprovidethemajorfoodforthegiantbluewhale,thelargestanimalevertoinhabittheEarth.Realizingthatthiswhalemaygrow100feetandweigh150tonsatmaturity,itisnotsurprisingthateachonedevoursmorethanonetonofkrilldaily.

Krillswimaboutjustbelowthesurfaceinhugeschoolssometimesmileswide,mainlyinthecoldAntarctic.Becauseoftheirpinkcolor,theyoftenappearasasolidreddishmasswhenviewedfromashiporfromtheair.Krillareveryhighinfoodvalue.Apoundofthesecrustaceanscontainsabout460calories—aboutthesameasshrimporlobster,towhichtheyarerelated.

Ifthekrillcanfeedsuchhugecreaturesaswhales,manyscientistsreason,theymustcertainlybecontendersasnewfoodsourceforhumans.

1.Whichofthefollowingbestportraystheorganizationofthepassage?

A.Theauthorpresentstheadvantagesanddisadvantagesofplanktonasafoodsource.

B.Theauthorquotespublicopiniontosupporttheargumentforfarmingplankton.

C.Theauthorclassifiesthedifferentfoodsourcesaccordingtoamountofcarbohydrate.

D.Theauthormakesageneralstatementaboutplanktonasafoodsourceandthenmovestoaspecificexample.

2.Accordingtothepassage,whyisplanktonregardedtobemorevaluablethanlandgrasses?

A.Itiseasiertocultivate.

B.Itproducesmorecarbohydrates.

C.Itdoesnotrequiresoil.

D.Itismorepalatable.

3.Whydoestheauthormention“planktonburgers”?

A.Todescribetheappearanceofonetypeofplankton.

B.Toillustratehowmuchplanktonawhaleconsumes.

C.Tosuggestplanktonasapossiblefoodsources.

D.Tocomparethefoodvaluesofbeefandplankton.

4.Whatismentionedasoneconspicuousfeatureofkrill?

A.Theyarethesmallestmarineanimals.

B.Theyarepinkincolor.

C.Theyaresimilarinsizetolobsters.

D.Theyhavegrasslikebodies.

5.Theauthormentionsallofthefollowingasreasonswhyplanktoncouldbeconsideredahumanfoodsourceexceptthatitis___.

A.highinfoodvalue.

B.inabundantsupplyintheoceans.

C.anappropriatefoodforotheranimals.

D.freeofchemicalsandpollutants.

Which is safer-staying at home， traveling to work on public transport， or working in the office? Surprisingly， each of these carries the same risk， which is very low. However， what about flying compared to working in the chemical industry? Unfortunately， the former is 65 times riskier than the latter! In fact， the accident rate of workers in the chemical industry is less than that of almost any of human activity， and almost as safe as staying at home.

The trouble with the chemical industry is that when things go wrong they often cause death to those living nearby. It is this which makes chemical accidents so newsworthy. Fortunately， they are extremely rare. The most famous ones happened at Texas City (1947)，Flixborough (1974)， Seveso (1976)， Pemex (1984) and Bhopal (1984)。

Some of these are always in the minds of the people even though the loss of life was small. No one died at Seveso， and only 28 workers at Flixborough. The worst accident of all was Bhopal， where up to 3，000 were killed. The Texas City explosion of fertilizer killed 552. The Pemex fire at a storage plant for natural gas in the suburbs of Mexico City took 542 lives， just a month before the unfortunate event at Bhopal.

Some experts have discussed these accidents and used each accident to illustrate a particular danger. Thus the Texas City explosion was caused by tons of ammonium nitrate(硝酸铵)，which is safe unless stored in great quantity. The Flixborough fireball was the fault of management， which took risks to keep production going during essential repairs. The Seveso accident shows what happens if the local authorities lack knowledge of the danger on their doorstep. When the poisonous gas drifted over the town， local leaders were incapable of taking effective action. The Pemex fire was made worse by an overloaded site in an overcrowded suburb. The fire set off a chain reaction os exploding storage tanks. Yet， by a miracle， the two largest tanks did not explode. Had these caught fire， then 3，000 strong rescue team and fire fighters would all have died.

1.Chemical accidents are usually important enough to be reported as news because ____.

A.they are very rare

B.they often cause loss of life

C.they always occur in big cities

D.they arouse the interest of all the readers

2.Which of the following statements is true?

A.Working at the office is safer than staying at home.

B.Traverlling to work on public transport is safer than working at the office.

C.Staying at home is safer than working in the chemical industry.

D.Working in the chemical industry is safer than traveling by air.

3.According to passage， the chemical accident that caused by the fault of management happened at ____.

A.Texas city B.Flixborough C.Seveso D.Mexico City

4.From the discussion among some experts we may coclude that ____.

A.to avoid any accidents we should not repair the facilities in chemical industry

B.the local authorities should not be concerned with the production of the chemical industry

C.all these accidents could have been avoided or controlled if effective measure had been taken

D.natural gas stored in very large tanks is always safe

5.From the passage we know that ammonium nitrate is a kind of ____.

A.natural gas， which can easily catch fire

B.fertilizer， which can't be stored in a great quantity

C.poisonous substance， which can't be used in overcrowded areas

D.fuel， which is stored in large tanks

Nearlyallthefamiliescanmanagetomeetthesoaringtuitioncoststhroughvariousinvestmentplans.

PartIVTranslation

Asthesourceofaluminumisalmostinexhaustible,wecanexpectthatmoreandmoreuseswillbefoundforthisversatilemetal.(PassageTwo)

Passage 3

Questions 11 to 15 are based on the following passage:

Unlike their American or European counterparts, car salesmen in Japan work hard to get a buyer. Instead of lying lazily around showrooms waiting for customers to drop by, many Japanese car salesmen still go out to get them. They walk wearily along the streets cars door-to-door. New customers are hunted with fruit and cakes on their birthdays. But life is getting tough, and not just because new-car sales are falling.

With more Japanese women (who often control the household budget) going out to work, the salesmen increasingly find nobody at home when they call. That means another visit in the evening or the weekend. Then they face an extra problem: more people, especially the young, prefer to choose a new car from a showroom where they can compare different models.

Even as late as the mid-1980s some 90% of new cars were sold door-to-door. In some rural areas most new cars are still sold this way. But in the big cities more than half the new cars are now sold from showrooms.

Although investing in showrooms is expensive because of the high cost of Japanese land, dealers have little choice. A labor shortage and higher among Japan’s workforce are making it difficult to hire door-to-door salesmen. Most of a Japanese car salesman’s working day is spent doing favors for customers, like arranging insurance or picking up vehicles for servicing, rather than actually selling.

Japan’s doorstep car salesmen are not about to vanish. The personal service they provide is so deep-rooted in Japan that they are likely to operate alongside the glittering new showrooms. The two systems even complement each other. What increasingly happens is that the showroom attracts the interest of a potential buyer, giving the footsore salesmen a firm lead to follow up with a home visit.

11. Japanese car sales usually do not wait at showrooms for customers to drop by; instead, .

A. they sell cars door-to-door

B. they buy presents for their customers

C. they enjoy themselves in recreation centers

D. they go out to do market researches

12. Implied but stated: the competition in car market is .

A. light B. moderate C. fierce D. unfair

13. Young people like to buy a new car .

A. at home B. from a showroom

C. made in the U.S.A. D. made in Japan

14. The squadron of Japanese car salesmen is reducing because of .

A. a labor shortage

B. higher expectations among Japan’s workforce

C. high cost land

D. both A and B

15. Japanese car salesmen to their customers many favors such as .

A. showing them around in an exhibition

B. arranging insurance

C. paying them a visit on weekends

D. selling ole cars for them