GMAT07perp语法笔记320题.doc

GMAT 07perp 语法笔记320题1.(24179-!-item-!-188;#058&000705)Although fullerenes-spherical molecules made entirely of carbon-were first found in the laboratory, they have since been found in nature, formed in fissures of the rare mineral shungite. Since laboratory synthesis of fullerenes requires distinctive conditions of temperature and pressure, this discovery should give geologists a test case for evaluating hypotheses about the state of the Earths crust at the time these naturally occurring fullerenes were formed.Which of the following, if true, most seriously undermines the argument?(A) Confirming that the shungite genuinely contained fullerenes took careful experimentation.(B) Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft.(C) The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed.(D) The naturally occurring fullerenes are arranged in a previously unknown crystalline structure.(E) Shungite itself is formed only under distinctive conditions.2.(24227-!-item-!-188;#058&000711)Economist: On average, the emergency treatment for an elderly person for injuries resulting from a fall costs $11,000. A new therapeutic program can significantly reduce an elderly persons chances of falling. Though obviously desirable for many reasons, this treatment program will cost $12,500 and thus cannot be justified.Which of the following, if true, most seriously undermines the conclusion of the argument?(A) Among elderly people who had followed the program for only a few months, the number of serious falls reported was higher than it was for people who had followed the program for its recommended minimum length of one year.(B) Falls resulting in serious injuries are less common among elderly people living in nursing homes than they are among elderly people who live alone at home.(C) A frequent result of injuries sustained in falls is long-term pain, medication for which is not counted among the average per-person costs of emergency treatment for elderly peoples injuries from such falls.(D) The new therapeutic program focuses on therapies other than medication, since overmedication can cause disorientation and hence increase the likelihood that an elderly person will have a serious fall.(E) A significant portion of the cost of the new therapeutic program is represented by regular visits by health care professionals, the costs of which tend to increase more rapidly than do those of other elements of the program.3.(24275-!-item-!-188;#058&000768)The prairie vole, a small North American grassland rodent, breeds year-round, and a group of voles living together consists primarily of an extended family, often including two or more litters. Voles commonly live in large groups from late autumn through winter; from spring through early autumn, however, most voles live in far smaller groups. The seasonal variation in group size can probably be explained by a seasonal variation in mortality among young voles.Which of the following, if true, provides the strongest support for the explanation offered?(A) It is in the spring and early summer that prairie vole communities generally contain the highest proportion of young voles.(B) Prairie vole populations vary dramatically in size from year to year.(C) The prairie vole subsists primarily on broad-leaved plants that are abundant only in spring.(D) Winters in the prairie voles habitat are often harsh, with temperatures that drop well below freezing.(E) Snakes, a major predator of young prairie voles, are active only from spring through early autumn.4.(24323-!-item-!-188;#058&000813)A popular beach has long had a dolphin feeding program in which fish are given to dolphins several times a day; many dolphins get as much as half of their food each day there. Although dolphins that first benefit from the program as adults are healthy and long-lived, their offspring have a lower life expectancy than offspring of dolphins that feed exclusively in the wild.Which of the following, if true, most helps to explain the lower life expectancy of offspring of dolphins feeding at the beach compared to other young dolphins?(A) Sharks that prey on dolphins are less common in the open seas off the beach than in many other areas of the open seas where dolphins congregate.(B) Many of the adult dolphins that feed at the beach are females that nurse their offspring there.(C) The fish given to the dolphins at the beach are the same types of fish that dolphins typically catch in the wild.(D) Many dolphins that feed at the beach with their offspring come to the beach only a few times a month.(E) Adult dolphins that feed at the beach spend much less time teaching their offspring how to catch fish in the wild than do other adult dolphins.5.(24371-!-item-!-188;#058&000859)Tiger sharks are common in the waters surrounding Tenare Island. Usually tiger sharks feed on smaller sharks, but sometimes they have attacked tourists swimming and surfing at Tenares beaches. This has hurt Tenares tourism industry, which is second only to its fishing industry in annual revenues. In order to help the economy, therefore, the mayor of the island has proposed an ongoing program to kill any tiger sharks within a mile of the beaches.Which of the following, if true, most strongly calls into question the likelihood that implementation of the mayors proposal will have the desired consequence?(A) Even if not all the tiger sharks that come close to the beaches are killed, the existence of the program would reassure tourists.(B) Business owners who depend on tourism are willing to pay most of the cost of implementing the program.(C) Tourists come to Tenare Island for its beaches, even though the island features a number of other tourist attractions.(D) The small sharks on which tiger sharks prey feed on fish that are commercially important to the islands fisheries.(E) Not all tourists who come to Tenare Island enjoy swimming or surfing.6.(24419-!-item-!-188;#058&000892)The country of Ertland has never imported apples in any significant quantity because consumers there generally prefer the unique texture of Ertland-grown apples. Nevertheless, apple growers from Kosolia, a neighboring country, plan to sell their apples in Ertland by selling Kosolia-grown apples at half the price of local apples and promoting them as a nourishing, low-cost alternative.Which of the following, if true, casts most doubt on the viability of the plan by Kosolias apple growers to sell their apples in Ertland?(A) Most of the varieties of apples grown in Ertland were originally derived from common Kosolian varieties.(B) Consumers in Ertland tend to spend about the same proportion of their income on fresh fruits and vegetables as do consumers in Kosolia.(C) At times in the past, Ertland has exported significant quantities of apples to Kosolia.(D) Some varieties of apples grown in Kosolia can be harvested throughout most of the year, whereas the varieties grown in Ertland can be harvested only during two months of the year.(E) Profiles of Ertland-grown apples are high enough in Ertland that growers, wholesalers, and retailers there could easily afford to reduce the price at which these apples are sold.7.(24651-!-item-!-188;#058&001089)As part of major renovations to Flowertowns Main Street train station, consultants to the train company proposed moving the stations entrance from its current valuable Main Street location to a low-rent adjoining side street and then leasing the high-rent entrance space to retail businesses. In that way, the train company could easily pay for those and all other proposed renovations without negative impact on its tight budget.Which of the following, if true, would most strongly support the consultants proposal?(A) More train commuters are employed in businesses located on Main Street than in businesses located on the adjoining side street.(B) A reliable survey of Flowertowns commuters showed that virtually none of them would use the train any less frequently if the stations entrance were moved.(C) The high-rent block of Flowertowns Main Street includes several buildings whose owners currently seek to replace long-standing tenants lost in recent months.(D) If the stations entrance were moved, the train company would need to begin costly renovations to its Main Street entrance space.(E) Ridership on Flowertown trains declined only slightly from 1970 to 1985 while other train companies lost large numbers of commuters.8.(24701-!-item-!-188;#058&001125)Automobile Dealers Advertisement:The Highway Traffic Safety Institute reports that the PZ 1000 has the fewest injuries per accident of any car in its class. This shows that the PZ 1000 is one of the safest cars available today.Which of the following, if true, most seriously weakens the argument in the advertisement?(A) The Highway Traffic Safety Institute report listed many cars in other classes that had more injuries per accident than did the PZ 1000.(B) In recent years many more PZ 1000s have been sold than have any other kind of car in its class.(C) Cars in the class to which the PZ 1000 belongs are more likely to be involved in accidents than are other types of cars.(D) The difference between the number of injuries per accident for the PZ 1000 and that for other cars in its class is quite pronounced.(E) The Highway Traffic Safety Institute issues reports only once a year.9.(24749-!-item-!-188;#058&001426)Scientists are discussing ways to remove excess carbon dioxide from the atmosphere by increasing the amount that is absorbed by plant life. One plan to accomplish this is to establish giant floating seaweed farms in the oceans. When the seaweed plants die, they will be disposed of by being burned for fuel.Which of the following, if true, would indicate the most serious weakness in the plan above?(A) Some areas of ocean in the Southern Hemisphere do not contain sufficient nutrients to support large seaweed farms.(B) When a seaweed plant is burned, it releases an amount of carbon dioxide comparable to the amount it has absorbed in its lifetime.(C) Even if seaweed farms prove effective, some people will be reluctant to switch to this new fuel.(D) Each year about seven billion tons of carbon dioxide are released into the atmosphere but only about five billion tons are absorbed by plant life.(E) Seaweed farms would make more money by farming seaweed to sell as nutritional supplements than by farming seaweed to sell as fuel.10.(25259-!-item-!-188;#058&001774)Jennifer: Video rental outlets in Centerville together handled 10,000 fewer video rentals in 1994 than in 1993. The decline in rentals was probably due almost entirely to the February 1994 opening of Videorama, the first and only video rental outlet in the area that, in addition to renting videos, also sold them cheaply.Brad: There must be another explanation: as you yourself said, the decline was on the order of 10,000 rentals. Yet Videorama sold only 4,000 videos in 1994.Which of the following, if true, would most seriously weaken the force of the objection that Brad presents to Jennifers explanation?(A) In 1994 Videorama rented out more videos than it sold.(B) In 1994 two new outlets that rent but that do not sell videos opened in Centerville.(C) Most of the video rental outlets in Centerville rent videos at a discount on certain nights of the week.(D) People often buy videos of movies that they have previously seen in a theater.(E) People who own videos frequently loan them to their friends.11.(25309-!-item-!-188;#058&001786)Mourdet Winery: Danville Winerys new wine was introduced to compete with our most popular wine, which is sold in a distinctive tall, black bottle. Danville uses a similar bottle. Thus, it is likely that many customers intending to buy our wine will mistakenly buy theirs instead.Danville Winery: Not so. The two bottles can be readily distinguished: the label on ours, but not on theirs, is gold colored.Which of the following, if true, most undermines Danville Winerys response?(A) Gold is the background color on the label of many of the wines produced by Danville Winery.(B) When the bottles are viewed side by side, Danville Winerys bottle is perceptibly taller than Mourdet Winerys.(C) Danville Winery, unlike Mourdet Winery, displays its wines label prominently in advertisements.(D) It is common for occasional purchasers to buy a bottle of wine on the basis of a general impression of the most obvious feature of the bottle.(E) Many popular wines are sold in bottles of a standard design.12.(25359-!-item-!-188;#058&001894)Finding of a survey of Systems magazine subscribers: Thirty percent of all merchandise orders placed by subscribers in response to advertisements in the magazine last year were placed by subscribers under age thirty-five.Finding of a survey of advertisers in Systems magazine: Most of the merchandise orders placed in response to advertisements in Systems last year were placed by people under age thirty-five.For both of the findings to be accurate, which of the following must be true?(A) More subscribers to Systems who have never ordered merchandise in response to advertisements in the magazine are age thirty-five or over than are under age thirty-five.(B) Among subscribers to Systems, the proportion who are under age thirty-five was considerably lower last year than it is now.(C) Most merchandise orders placed in response to advertisements in Systems last year were placed by Systems subscribers over age thirty-five.(D) Last year, the average dollar amount of merchandise orders placed was less for subscribers under age thirty-five than for those age thirty-five or over.(E) Last year many people who placed orders for merchandise in response to advertisements in Systems were not subscribers to the magazine.13.(26741-!-item-!-188;#058&002910)Which of the following most logically completes the argument?United States manufacturers currently produce most of the worlds solar-power generators-most of which are exported to Europe. However, European manufacturers are emerging and probably will ultimately capture much of the European market. The United States government is funding initiatives intended to encourage use of solar power within the United States. If these initiatives succeed in increasing the demand for solar-power generators in the United States, United States manufacturers will probably maintain significant production levels, since _.(A) some United States manufacturers have been substantially increasing their output over the last several years(B) the efficiency of solar-power generators in converting energy from the Sun into electric power is not improving as fast as it once did(C) just as European manufacturers enjoy certain competitive advantages in Europe, so do United States manufacturers in the United States(D) European governments are currently undertaking initiatives to stimulate the use of solar power within Europe(E) the current market for solar-power generators in the United States is very limited14.(26835-!-item-!-188;#058&002982)The higher the level of certain vitamins and minerals in the bloodstream, the better a persons lung function, as measured by the amount of air the person can expel in one second. The lung function of smokers is significantly worse, on average, than that of nonsmokers. Clearly, therefore, one way for smokers to improve their lung function is for them to increase their intake of foods that are rich in these helpful vitamins and minerals.Which of the following is an assumption on which this argument depends?(A) Smokers are less likely than nonsmokers to have diets that are rich in vitamins and minerals.(B) The lung function of smokers whose diets are rich in those vitamins and minerals is generally better than that of nonsmokers with comparable diets.(C) People whose diets are deficient in those vitamins and minerals do not typically have other health problems in addition to diminished lung function.(D) Stopping smoking will not typically improve lung function more than any diet changes can.(E) Smoking does not introduce into the body chemicals that prevent the helpful vitamins and minerals from entering the bloodstream.15.(26883-!-item-!-188;#058&002985)GWD #29-Q28Astronomer: Observations of the Shoemaker-Levi comet on its collision course with Jupiter showed that the comet broke into fragments before entering Jupiters atmosphere in 1994, but they did not show how big those fragments were. In hopes of gaining some indication of the fragments size, astronomers studied spectrographic analyses of Jupiters outer atmosphere. These analyses revealed unprecedented traces of sulfur after the fragments entry. The fragments themselves almost certainly contained no sulfur, but many astronomers believe that the cloud layer below Jupiters outer atmosphere does contain sulfur. Since sulfur would have seeped into the outer atmosphere if comet fragments had penetrated this cloud layer, it is likely that some of the fragments were at least large enough to have passed through Jupiters outer atmosphere without being burned up.In the astronomers argument, the two portions in boldface play which of the following roles?(A) The first presents a circumstance for which the astronomer offers an explanation; the second is part of that explanation.(B) The first acknowledges a consideration that weighs against the conclusion of the argument; the second is that conclusion.(C) The first acknowledges a consideration that weighs against the conclusion of the argument; the second provides evidence in support of that conclusion.(D) The first provides evidence in support of the conclusion of the argument; the second acknowledges a consideration that weighs against that conclusion.(E) The first is a judgment advanced in support of the conclusion of the argument; the second is that conclusion.16.(27621-!-item-!-188;#058&003223)Most of the worlds supply of uranium currently comes from mines. It is possible to extract uranium from seawater, but the cost of doing so is greater than the price that uranium fetches on the world market. Therefore, until the cost of extracting uranium from seawater can somehow be reduced, this method of obtaining uranium is unlikely to be commercially viable.Which of the following would it be most useful to determine in evaluating the argument?(A) Whether the uranium in deposits on land is rapidly being depleted(B) Whether most uranium is used near where it is mined(C) Whether there are any technological advances that show promise of reducing the cost of extracting uranium from seawater(D) Whether the total amount of uranium in seawater is significantly greater than the total amount of uranium on land(E) Whether uranium can be extracted from freshwater at a cost similar to the cost of extracting it from seawater17.(27669-!-item-!-188;#058&003302)Urban air contains more sulfur dioxide than does rural air, and plants in cities typically grow more slowly than do plants in rural areas. In an experiment to see how much of the difference in growth is due to sulfur dioxide, classes in an urban and a rural school grew plants in greenhouses at their schools and filtered the greenhouse air to eliminate sulfur dioxide. Plants in the urban greenhouse grew more slowly than those in the rural greenhouse.Which of the following, if true, would it be most important to take into account in evaluating the resul