大家论坛四六级http:/club.topsage.com/forum-58-1.htmlWe can begin our discussion of"population as global issue"with what most persons mean when they discuss"the populationproblem":too many people on earth and a too rapid increase in the number added each year.The facts are not in dispute,It wasquite right to employ the analogy that likened demographic growth to"a long,thin powder fuse that burns steadily and haltinglyuntil it finally reaches the charge and explodes."To understand the current situation,which is characterized by rapid increases in population,it is necessary to understand thehistory of population trends.Rapid growth is a comparatively recent phenomenon.Looking back at the 8,000 years ofdemographic history,we find that populations have been virtually stable or growing very slightly for most of human history.For most of our ancestors,life was hard,often nasty,and very short.There was high fertility in most places,but this wasusually balanced by high mortality.For most of human history,it was seldom the case that one in ten persons would live pastforty,while infancy and childhood were especially risky periods.Often,societies were in clear danger of extinction becausedeath rates could exceed their birthrates.Thus,the population problem throughout most of history was how to preventextinction of the human race.This pattem is important to notice.Not only does it put the current problems of demographic growth into a historicalperspective,but it suggests that the cause of rapid increase in population in recent years is not a sudden enthusiasm for morechildren,but an improvement in the conditions that traditionally have caused high mortality.Demographic history can be divided into two major periods:a time of long,slow growth which extended from about 8,000BC.till approximately AD.1650.In the first period of some 9600 years,the population increased from some 8 million to 500million in 1650.Between 1650 and the present,the population has increased from 500 million to more than 4 billion.And it isestimated that by theyear 2000 there will be 6.2 billion people throughout the world.One way to appreciate this dramatic difference in such abstractnumbers is to reduce the time frame to something that is more manageable.Between 8000BC and 1650,an average of only50,000 persons was being added annually to the world's population each year.At present,this number is added every six hours.The increase is about 80,000,000 persons annually.1.Which of the following demographic growth pattern isB.About 50,000 babies are born every six hours at present.most suitable for the long thin powder fuse analogy?C.Between 8000 BC and the present,the population increaseA.A virtually stable or slightly decreasing period and then ais about 80,000,000 persons each year.sudden explosion of population.D.The population increased faster between 8000BC andB.A slow growth for a long time and then a period of rapid,1650 than between 1650 and the present.dramatic increase.C.Too many people on earth and a few rapid increase in the4.The author of the passage intends tonumber added each year.A.warn people against the population explosion in the nearD.A long period when death rates exceeds birthrates and thenfuture.a short period with higher fertility and lower mortality.B.compare the demographic growth pattem in the past withthat after 16502.During the first period of demographic history,societiesC.find out the cause for rapid increase in population in recentwere often in danger of extinction becauseyears.A.only one in ten persons could live past 40.D.present us a clear and complete picture of the demographicB.there was higher mortality than fertility in most places.growth.C.it was too dangerous to have babies due to the poorconditions.5.The word "demographic"in the first paragraph meansD.our ancestors had little enthusiasm for more childrenA.statistics of humanB.surroundings study3.Which statement is true about population increase?C.accumulation of humanA.There might be an increase of 2.2 billion persons fromD.development of human.now to the year 2000.答案：ABADAMost of us are taught to pay attention to what is said-the words.Words do provide us with some information,but meaningsare derived from so many other sources that it would hinder our effectiveness as a partner to a relationship to rely too heavilyon words alone.Words are used to describe only a small part of the many ideas we associate with any given message.Sometimes we can gain insight into some of those associations if we listen for more than words.We don't always say what wemean or mean what we say.Sometimes our words don't mean anything except"I'm letting off some steam.I don't really wantyou to pay close attention to what I'm saying.Just pay attention to what I'm feeling."Mostly we mean several things at once.Aperson wanting to purchase a house says to the current owner,"This step has to be fixed before I'll buy."The owner says,"It'sbeen like that for years."Actually,the step hasn't been like that for years,but the unspoken message is:"I don't want to fix it.大家论坛四六级http://club.topsage.com/forum-58-1.html大家论坛四六级http://club.topsage.com/forum-58-1.htmlWe put up with it.Why can't you?"The search for a more expansive view of meaning can be developed of examining amessage in terms of who said it,when it occurred,the related conditions or situation,and how it was said.When a message occurs can also reveal associated meaning.Let us assume two couples do exactly the same amount ofkissing and arguing.But one couple always kisses after an argument and the other couple always argues after a kiss.Theordering of the behaviors may mean a great deal more than the frequency of the behavior.A friend's unusually docile behaviormay only be understood by noting that it was preceded by situations that required an abnommal amount of assertiveness.Someresponses may be directly linked to a developing pattem of responses and defy logic.For example,a person who says"No!"toa serials of charges like"You're dumb,”“You're lazy,”and“You're dishonest,”may also say "No!”and try to justify his or herresponse if the next statement is "And you're good looking."We would do well to listen for how messages are presented.The words,"If sure has been nice to have you over,"can be saidwith emphasis and excitement or ritualistically.The phrase can be said once or repeated several times.And the meanings weassociate with the phrase will change accordingly.Sometimes if we say something infrequently it assumes more importance;sometimes the more we say something the less importance it assumes1.Effective communication is rendered possible betweenC.the condition of the step is only a minor fault.two conversing partners,ifD.the cost involved in the fixing should be shared.A.they use proper words to carry their ideas.B.they both speak truly of their own feelings.4.Some responses and behaviors may appear very illogical,C.they try to understand each other's ideas beyond words.but are justifiable ifD.they are capable of associating meaning with their words.A.linked to an abnormal amount of assertiveness.B.seen as one's habitual pattern of behavior.2."I'm letting off some steam"in paragraph 1 meansC.taken as part of an ordering sequence.A.I'm just calling your attention.D.expressed to a series of charges.B.I'm just kidding.C.I'm just saying the opposite.5.The word "ritualistically"in the last paragraph equalsD.I'm just giving off some sound.something doneA.without true intention3.The house-owner's example shows that he actuallyB.light-heartedly.meansC.in a way of ceremony.A.the step has been like that for years.D.with less emphasis.B.he doesn't think it necessary to fix the step答案：DBABCA controversy erupted in the scientific community in early 1998 over the use of DNA(deoxyribonucleic acid fingerprintingin criminal investigations.DNA fingerprinting was introduced in 1987 as a method to identify individuals based on a patternseen in their DNA,the molecule of which genes are made.DNA is present in every cell of the body except red blood cells.DNA fingerprinting has been used successfully in various ways,such as to determine paternity where it is not clear who thefather of a particular child is.However,it is in the area of criminal investigations that DNA fingerprinting has potentiallypowerful and controversial uses.DNA fingerprinting and other DNA analysis techniques have revolutionized criminal investigations by giving investigatorspowerful new tools in the attempt to trove guilt,not just establish innocence.When used in criminal investigations,a DNAfingerprint pattern from a suspect is compared with a DNA fingerprint pattem obtained from such material as hairs or bloodfound at the scene of a crime.A match between the two DNA samples can be used as evidence to convict a suspect.The controversy in 1998 stemmed form a report published in December 1991 by population geneticists Richard C.Lewontin of Harvard University in Cambridge,Mass.,and Daniel L.Hartl called into question the methods to calculate howlikely it is that a match between two DNA fingerprints might occur by chance alone.In particular,they argued that the currentmethod cannot properly determine the likelihood that two DNA samples will match because they came from the sameindividual rather than simply from two different individuals who are members of the same ethnic group.Lewontin and Hartlcalled for better surveys of DNA pattems methods are adequate.In response to their criticisms,population geneticists Ranajit Chakraborty of the University of Texas in Dallas and KennethK.Kidd of Yale University in New Haven,Conn.,argued that enough data are already available to show that the methodscurrently being used are adequate.In January 1998,however,the federal Bureau of Investigation and laboratories that conductDNA tests announced that they would collect additional DNA samples form various ethnic groups in an attempt to resolvesome of these questions.And,in April,a National Academy of Sciences called for strict standards and system of accreditationfor DNA testing laboratories.1.Before DNA fingerprinting is used,suspectsinvestigationsA.would have to leave their fingerprints for furtherB.would have to submit evidence for their innocence大家论坛四六级http:/club.topsage.com/forum-58-1.html大家论坛四六级http:/club.topsage.com/forum-58-1.htmlC.could easily escape conviction of guilt4.The attitude of the Federal Bereau of Investigation showsD.cold be convicted of guilt as wellthatA.enough data are yet to be collected form various ethnic2.DNA fingerprinting can be unreliable whengroups to confirm the unlikelihood of two DNA samplesA.the methods used for blood-cell calculation are notcoming from two individual membersaccurateB.enough data of DNA samples should be collected toB.two different individuals of the same ethnic group mayconfirm that only DNA samples form the same person canhave the same DNA fingerprinting patternmatchC.a match is by chance left with fingerprints that happen toC.enough data are yet to be collected from various ethnicbelong to two different individualsgroups to determine the likelihood of two different DNAD.two different individuals leave two DNA samplessamples coming fomm the same personD.additional samples from various ethnic groups should be3.To geneticists like Lewontin and Hartl,the currentcollected to determine that two DNA samples are unlikely tomethodcome from the same personA.is not so convincing as to exclude the likelihood that twoDNA samples can never come from two individuals5.National Academy of Sciences holds the stance thatB.is arguable because two individuals of the same ethnicA.DNA testing should be systematizedgroup are likely to have the same DNA pattern.B.Only authorized laboratories can conduct DNA testingC.Is not based on adequate scientific theory of geneticsC.The academy only is authorized to work out standards forD.Is theoretically contradictory to what they have beentestingstudyingDNA testing答案：CBABB4Racket,din clamor,noise,whatever you want to call it,unwanted sound is America's most widespread nuisance.But noise ismore than just a nuisance.It constitutes a real and present danger to people's health.Day and night,at home,at work,and atplay,noise can produce serious physical and psychological stress.No one is immune to this stress.Though we seem to adjust tonoise by ignoring it,the ear,in fact,never closes and the body still responds-sometimes with extreme tension,as to a strangesound in the night.The annoyance we feel when faced with noise is the most common outward symptom of the stress building up inside us.Indeed,because irritability is so apparent,legislators have made public annoyance the basis of many noise abatement programs.The more subtle and more serious health hazards associated with stress caused by noise traditionally have been given much lessattention.Nevertheless,when we are annoyed or made irritable by noise,we should consider these symptoms fair warning thatother thing may be happening to us,some of which may be damaging to our health.Of many health hazards to noise,hearing loss is the most clearly observable and measurable by health professionals.Theother hazards are harder to pin down.For many of us,there may be a risk that exposure to the stress of noise increasessusceptibility to disease and infection.The more susceptible among us may experience noise as a complicating factor in heartproblems and other diseases.Noise that causes annoyance and irritability in health persons may have serious consequences forthese already ill in mind or body.Noise affects us throughout our lives.For example,there are indications of effects on the unborn child when mothers areexposed to industrial and environmental noise.During infancy and childhood,youngsters exposed to high noise levels mayhave trouble falling asleep and obtaining necessary amounts of rest.Why,then,is there not greater alarm about these dangers?Perhaps it is because the link between noise and many disabilitiesor diseases has not yet been conclusively demonstrated.Perhaps it is because we tend to dismiss annoyance as a price to pay forliving in the modern world.It may also be because we still think of hearing loss as only an occupational hazard.1.In Paragraph 1,the phrase "immune to"are used toD.hystericalmeanA.unaffected by3.Which of the following best states the main idea of theB.hurt bypassage?C.unlikely to be seen byA.Noise is a major problem;most people recognize itsD.unknown byimportance.B.Although noise can be annoying,it is not a major problem.2.The author's attitude toward noise would best be describedC.Noise is a major problem and has not yet been recognizedasas such.A.unrealisticD.Noise is a major problem about which nothing can be done.B.traditionalC.concemed4.The author condemns noise essentially because it大家论坛四六级http://club.topsage.com/forum-58-1.html