America has now adopted more ________ European-style. inspection systems, and the incidence of food poisoning is falling.

A) discrete

B) solemn

C) rigorous

D) autonomous

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• What is the argunent of Monsanto and its supporters?

  A.Patent rights should be protected to encourage innovation.

  B.Bowman cannot plant the seeds without Monsantos consent.

  C.Monsanto has the right to recover the costs of its patented seeds.

  D.Patent law on genetically modified seeds should not be challenged.

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• If our solar system has a Hell, it's Venus. The air is choked with foul and corrosive sulfur, heaved from ancient volcanoes and feeding acid clouds above. Although the second planet is a step farther from the sun than Mercury, a runaway greenhouse effect makes it hotter indeed. It's the hottest of the nine plants, a toasty 900 degrees Fahrenheit of baking rocky flats from equator to poles. All this under a crushing atmospheric pressure 90 times that of where you're sitting now. From the earthly perspective, a dead end. It must be lifeless.

  "Venus has nothing," is the blunt word from planetologist Kevin Zahnle of NASA Ames Research Center in Calitfornia's Silicon Valley. "We've written it off."

  Yet a small group of advanced life-forms on Earth begs to differ, and theorizes that bizarre microbial ecosystems might have once populated Venus and, in fact, may be there still. Members of this loose band of researchers suggest that their colleagues have water too much on the brain, and are, in a sense, H2O chauvinists (盲目的爱国者).

  "Astrobiologists are neglecting Venus due more to narrow thinking than actual knowledge of the environment, or environments, where life can thrive," says Dirk Schulze-Makuch, a geobiologist at the University of Texas at E1 Paso who recently co-authored a Venus-boosting paper in Astrobiology with colleague Louis Irwin.

  The bias against life on Venus is partly rooted in our own biology. Human experience instructs that liquid water, preferably lot of it, is essential for life. In search for extraterrestrial life, we obsess over small rivers in Mars' surface apparently carved by ancient gushes of water, and delight in hints of permafrost (永久冻结带) just underneath its surface. (By comparison, Venus isn't even that interesting to look at: A boring cue ball (台球的白色母球) for backyard astronomers, its clouds reflects 75% of visible light.) Attention and then funding follow the water: Three more landers will depart for Mars this spring, and serious plans for sample-return missions hover in the midterm future.

  "If you have limited resources, you base exploration on what you know," says Arizona State University planetary geologist Ronal Greeley. It's like losing your keys on the way home at night: The first place you look is under the streetlights not because they're more likely to be there, but because if they are, you'll spot them. For astrobiologists, the streetlights are the spectral (光谱的)lines for water, and they've spotted that potential on Mars, Jupiter's moon Europa, even Neptune's moon Triton. Not on the baking rocky flats of Venus.

  Venus is the hottest of all the nine planets in the solar system because______.

  A．it is not so close to the Sun as Mercury

  B．many volcanoes spread the whole planet

  C．it is covered by a thick layer of cloud

  D．greenhouse effect is uncontrollable on it

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• 听力原文： Throughout history man has changed his physical environment in order to improve his way of life.

  With the tools of technology he has altered many physical features of the earth. He has transformed wood lands into farmland, and made lakes and reservoirs out of rivers for irrigation purposes or hydroelectric power. Man has also modified the face of the earth by draining marshes and cutting through mountains to build roads and railways.

  However, man's changes to the physical environment have not always had beneficial results. Today, pollution of the air and water is an increasing danger to the health of the planet. Each day thousands of tons of gases come out of the exhausts of motor vehicles; smoke from factories pollutes the air of industrialized areas and the surrounding areas of countryside. The air in cities is becoming increasingly unhealthy.

  The pollution of water is equally harmful. In the sea, pollution from oil is increasing and is killing enormous numbers of algae ( a very simple plant without stems or leaves that grows in or near water), fish and birds. The whole ecological balance of the sea is being changed. The same problem exists in rivers, Industrial wastes have already made many rivers lifeless.

  Conservationists believe that it is now necessary for man to limit the growth of technology in order to survive on earth.

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  A．Bettering his way of life.

  B．Improving his surroundings.

  C．Modifying the face of the planet.

  D．Altering the physical features of the earth.

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• In ________ times human beings did not travel for pleasure but to find a more favourable climate.

  A) prime

  B) primitive

  C) primary

  D) preliminary

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• It was in 1930s that scientists first ______ the idea of the atom bomb.

  A．imagined

  B．contemplated

  C．reckoned

  D．conceived

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