Special trees that grow faster, fight pollution, produce better wood, and even sense chemical attacks are being planted by scientists in the US．

       When 40 per cent of Hawaii's US$14 million-a-year papaya （木瓜）industry was destroyed by a virus five years ago, work began on creating genetically engineered （轉(zhuǎn)基因的） trees．

       Researchers successfully introduced seeds that were designed to resist the virus．Since then, more and more people have been testing genetically engineered trees．

       Some researchers put special bacteria into trees to help them grow faster and produce better wood．Others are trying to create trees that can clean polluted soil．

       Meanwhile fruit farmers are looking for trees that are strong enough to resist worms, and paper companies want trees that produce more wood and therefore more paper．

       The Pentagon （五角大樓） even gave the researchers US$500,000 this year after they developed a pine tree that changes its colours if it senses a chemical attack．

       So far, the poplar, eucalyptus （楊樹與桉樹）, apple and coffee trees are among those being engineered．All this can be done today because we have a better understanding of tree genomes （基因組）．

       However, some people fear that the genetically engineered trees will cause dangerous results．They are worried that the new trees will breed with natural species and change the balance of the forest environment．

       "It could be destructive," said Jim Diamond, an environmentalist．"Trees are what is left of our natural environment and home to many endangered species．"

       But researchers insist that science could give nature a fighting chance against both natural and man-made dangers．

       They hope to answer the critics by stopping the new trees from breeding, so their effect on the environment can be controlled．

1．Which kind of tree is not the ones that scientists are planting in the US?

       A．Trees that worms can't hurt．

       B．Trees that can protect themselves at a chemical attack．

       C．Trees that can resist wind better．

       D．Genetically engineered trees．

2．What caused the American scientists to work on special trees?

       A．They think science could give nature a fighting chance against both natural and man-made dangers．

       B．Great numbers of trees have been lost due to attacks by viruses．

       C．Researchers successfully introduced seeds designed to resist the virus．

       D．Tree genomes are mapped out so scientists know how to improve trees．

3．Which of the following was probably the first kind of trees being engineered?

       A．Papaya．            B．Pine．                 C．Apple．              D．Poplar．

4．Why did critics think engineered trees dangerous? Because _______．

       A．these trees can destroy the balance of nature

       B．everything except trees has been genetically engineered

       C．trees are home to many endangered species

       D．these trees may affect normal trees

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科目：高中英語 來源：高考三人行·英語 題型：014

These bears feed ________ the leaves of this special tree.

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科目：高中英語 來源： 題型：閱讀理解

New Year and Its Celebrations（新年習(xí)俗）?
January 1,the beginning of a New Year.?
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B.The people of ancient Babylon began their New Year on March 21,the first day of spring.?
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D.The people of ancient Persia began their New Year in late summer.?
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科目：高中英語 來源：河南省唐河三高2009-2010學(xué)年高一下學(xué)期期末模擬試題（英語） 題型：閱讀理解

Do you know why different animals or pests have their special colours? Colours in them seem to be used mainly to protect themselves.

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If you study the animal life, you'll find the main use of colouring is protecting themselves. Bears, lions and other animals move quietly through forests. They cannot be seen by hunters. This is because they have the colours much like the tree.

Have you ever noticed an even more strange act? A kind of fish in the sea can send out a kind of very black liquid when it faces danger. While the liquid spread over, the enemies cannot find it. And it immediately swims away. So it has lived up to now though it isn't strong at all.

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A. are small animals

B. are easily found by birds

C. are dangerous to their enemies

D. change their colours to protect themselves

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A. They run away quickly.

B. They colours much like their enemies.

C. They hide themselves in the day and appear at night.

D. They have to move quietly.

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A. The Change of Colours for Animals and Pests

B. Colours of Different Animals and Pests

C. The Main Use of Colours for Animals and Pests

D. Some Animals and Pests

 

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Coffee experts are willing to pay large sums of money for high-quality coffee beans. The high-end beans, such as Kona or Blue Mountain, are known to cost extraordinary sums of money. Then there is Kopi Lowak (translated as “Civet Coffee”), the world’s most expensive coffee, which sells for as much as US $50 per quarter-pound.

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1.What does “This” in the second paragraph refer to?

A. Civet Coffee.                            B. Blue Mountain coffee.

C. The high price of Kopi Lowak.            D. The unique taste of Kona.

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D. How palm civets change coffee fruit to Kopi Lowak beans.

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A. Little palm civets eat only the outer layer of the coffee cherries.

B. Palm civets somehow know the right time when the coffee fruit ripens.

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D. Kona and Blue Mountain are the most expensive coffees but only of average quality.

 

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