3、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，美國國防部所在地） 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 is 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

1、目前，許多學(xué)校對(duì)學(xué)生采取封閉式管理，學(xué)生對(duì)此看法不一。請(qǐng)根據(jù)下表所提供的信息，寫一篇短文，談?wù)勛约旱目捶�。（字�(jǐn)?shù)120左右）

注意：1．不要逐字翻譯。2短文開頭已給出，不計(jì)人總詞數(shù)。

Nowadays a lot of schools keep their students in school all day long．……

28、—Where is your brother?

—I think he's still in       bed，but he might just be in       bathroom．

A．/; /          B．the; the             C．the;/                   D．/; the

27、The thieves ran away separately，       carrying a bag．The police then divided into groups to follow them immediately．

A．a(chǎn)ll         B．each         C．every        D．either

24、—What a wonderful speech he made!

—Really good! I could hardly imagine myself        to make a speech in public.

A．make         B．to make          C．making          D．being made