[单项选择]Mycorrhizal fungi infect more plants than do any other fungi and are necessary for many plants to thrive, but they have escaped widespread investigation until recently for two reasons. First, the symbiotic association is so well-balanced that the roots of host plants show no damage even when densely infected. Second, the fungi cannot as yet be cultivated in the absence of a living root. Despite these difficulties, there has been important new Work that suggests that this symbiotic association can be harnessed to achieve more economical use of costly superphosphate fertilizer and to permit better exploitation of cheaper, less-soluble rock phosphate. Mycorrhizal benefits are not limited to improved phosphate uptake in host plants. In legumes, mycorrhizal inoculation has increased nitrogen fixation beyond levels achieved by adding phosphate fertilizer alone. Certain symbiotic associations also increase the host plant’s resistance to harmful root fungi. Whether this resistance results from
A. a description of a replicable experiment
B. a refutation of an earlier hypothesis
C. a summary report of new findings
D. a confirmation of earlier research

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[单项选择]Mycorrhizal fungi infect more plants than do any other fungi and are necessary for many plants to thrive, but they have escaped widespread investigation until recently for two reasons. First, the symbiotic association is so well-balanced that the roots of host plants show no damage even when densely infected. Second, the fungi cannot as yet be cultivated in the absence of a living root. Despite these difficulties, there has been important new Work that suggests that this symbiotic association can be harnessed to achieve more economical use of costly superphosphate fertilizer and to permit better exploitation of cheaper, less-soluble rock phosphate. Mycorrhizal benefits are not limited to improved phosphate uptake in host plants. In legumes, mycorrhizal inoculation has increased nitrogen fixation beyond levels achieved by adding phosphate fertilizer alone. Certain symbiotic associations also increase the host plant’s resistance to harmful root fungi. Whether this resistance results from
A. lack of funding for such research
B. lack of immediate application of such research
C. difficulties surrounding laboratory production of specimens for study.
D. lack of a method for identifying mycorrhizal fungi

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[单项选择]Passage Four

Mycorrhizal fungi infect more plants than do any other fungi and are necessary for many plants to thrive, but they have escaped widespread investigation until recently for two reasons. First, the symbiotic association is so well-balanced that the roots of host plants show no damage even when densely infected. Second, the fungi cannot as yet be cultivated in the absence of a living root. Despite these difficulties, there has been important new Work that suggests that this symbiotic association can be harnessed to achieve more economical use of costly superphosphate fertilizer and to permit better exploitation of cheaper, less-soluble rock phosphate. Mycorrhizal benefits are not limited to improved phosphate uptake in host plants. In legumes, mycorrhizal inoculation has increased nitrogen fixation beyond levels achieved by adding pho
A. a description of a replicable experiment
B. a refutation of an earlier hypothesis
C. a summary report of new findings
D. a confirmation of earlier research

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[单项选择]Passage 1 Britain almost more than any other country in the world must seriously face the problem of building upwards，that is to say of accommodating a considerable proportion of its population in high blocks of flats．It is said that the Englishman objects to this type of existence，but if the case is such, he does in fact differ from the inhabitants of most countries of the world today．In the past our own blocks of flats have been associated with the lower-income groups and they have lacked the obvious provisions，such as central heating，constant hot water supply, electrically operated lifts from top to bottom，as well as such details，important notwithstanding(然而)，as easy facilities for disposal of dust and rubbish and storage places for baby carriages on the ground floor, playgrounds for children on the top of the buildings，and drying grounds for washing．It is likely that the dispute regarding flats versus(对抗)individual houses will continue to rage on for a long time as far as Brit
A. English people，like most people in other countries，dislike living in flats
B. people in most countries of the world today are not opposed to living in flats
C. people in Britain are forced to move into high blocks of flats
D. modern flats still fail to provide the necessary facilities for living

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[单项选择]Text 4

More than any other industry, the luxury-goods business needs people to feel good about spending money. So at a recent conference in Moscow, Bernard Arnault, the head of Moet Hennessy Louis Vuitton (LVMH), the world’s biggest luxury-goods group, went to great lengths to dismiss investors’ fears about the impact on the industry of America’s credit crisis, a possible recession and the weak dollar. Indeed, Mr. Arnault said he expects the industry’s sales almost to double in the next five years, thanks to strong demand from emerging markets and the creation of new wealth across the globe.
After a depressing period at the beginning of the decade when the terrorist attacks in America, the outbreak of SARS and the war in Iraq reduced international travel and people’s appetite for frivolous things, the industry has had three excellent years
A. Newly developed markets such as Asia.
B. Markets with customers being merely affluent.
C. Markets in developing countries.
D. New market in European and American countries.

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