题目内容

Some plants get so hungry they eat flies,spiders,and even small frogs. What's more amazing is that these plants occur naturally (in special environments) in every state. In fact,they're found on every continent except Antarctica.

You've probably seen a Venus' flytrap (捕蝾草) .It's often sold in museum gift stores,de?partment stores,and even supermarkets. A small plant,it grows 6 to 8 inches tall in a contain?er. At the end of its stalks (茎) are specially modified leaves that act like traps. Inside each trap is a lining of tiny trigger (触发) hairs. When an insect lands on them,the trap suddenly shut. Over the course of a week or so,the plant feeds on its catch.

The Venus' flytrap is just one of more than 500 species of meateating plants,says Barry Meyers-Rice,the editor of the International Carnivorous Plant Society's Newsletter. Note: Despite any sciencefiction stories (科幻小说) you might have read,no meateating plant does any danger to humans.

Dr. Meyers-Rice says a plant is meateating,only if it does all four of the following: " at?tract,kill,digest,and absorb" some form of insects,including flies,butterflies,and moths. Meateating plants look and act like other green plants―well,most of the time.

All green plants make sugar through a process called photosynthesis (光合作用) .Plants use the sugar to make food. What makes " meateating" plants different is their bugcatching leaves. They need insects for one reason;nitrogen (氮) .Nitrogen is a nutrient that they can't obtain by any other way. Why?

Almost all green plants on our planet get nitrogen from the soil. " Meateating" plants can't. They live in places where nutrients are hard or almost impossible to get from the soil be?cause of its acidity (酸度) .So they've come to rely on getting nitrogen from insects and small animals. In fact,nutrientrich soil is poisonous to "meateating" plants. Never fertilize (施肥) them!But don't worry,either,if they never seem to catch any insects. They can survive,but they'll grow very slowly.

(   ) 1. What is a Venus flytrap?

   A. It is a small plant which grows in a container.

   B. It grows 6-8 inches tall.

   C. It can attract,kill,digest and absorb some form of insects.

   D. It is a kind of plant which gets hungry easily.

(   ) 2. What can we learn from the passage?

   A. It is the bugcatch leaves make Venus flytrap different from other plants.

   B. All green plants get nitrogen from the soil.

   C. " Meateating" plants are found on every continent.

   D. Some "meateating" plants in the world do danger to humans.

(   ) 3. Why does the writer say "Never fertilize ' meateating' plants?"

   A. Though growing slowly,they don't need nitrogen.

   B. Probably because the source of nitrogen is adequate.

   C. Simply because the nutrientrich soil will do harm to them.

   D. Perhaps they can get fertilize by themselves.

(   ) 4. Which of the following might be the best title for the text?

   A. Meateating Plant Does No Danger to Humans

   B. Let These Plants Swat (重击) the Bugs for You

   C. No Need to Fertilize Meateating Plants

   D. No Insects,No "Meateating" Plants

CACB

有些植物捕获小昆虫为自身增加养分。

1. C细节理解题。第四段有详细表述。

2. A推理判断题。其他三项都是错的。

3. C细节理解题。

4. B主旨大意题。虽然没有直接表述,B项从另一个角度说明一些植物能够帮助人类摆脱恼人的小昆虫。其他选择不能代表整篇文章的主题。

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British Columbia is the third largest Canadian provinces,both in area and population. It is nearly 1. 5 times as large as Texas,and 1       800 miles (1,280km) north from the United States border. It includes Canada's entire west coast and the islands just 2        the coast.

Most of British Columbia is mountainous,with long rugged ranges 3        north and south. Even the coastal islands are the 4        of a mountain range that existed thousands of years ago. During the last Ice Age,this range was scoured by glaciers until most of 5       was 6       the sea. Its peaks now show as islands 7        along the coast.

The southwestern coastal region has a humid mild marine 8       . Sea winds that blow in?land from the west are warmed by a current of warm water that flows 9        the Pacific Ocean. As a result,winter temperatures average above 10        and summers are mild. These warm western winds also carry 11        from the ocean.

Inland from the coast,the winds from the Pacific 12        the mountain barriers of the coast?al ranges and the Rocky Mountains. As they 13        to cross the mountains,the winds are cooled,and their moisture begins to fall as 14       ,On some of the western slopes almost 200 inches (500cm) of rain fall each year.

More than half of British Columbia is 15        forested. On mountain slopes that receive plentiful rainfall,huge Douglas firs rise in towering columns. These 16       giants often grow to be as much as 300 feet (90m) tall,17       diameters up to 10 feet (3m) . More lumber is 18        from these trees than from any other kind of trees in North 19       . Hemlock,red cedar,and balsam fir are among the other trees 20        in British Columbia.

(   ) 1. A. spreads   B. increases   C. extends   D. continues

(   ) 2. A. away   B. of   C. off   D. from

(   ) 3. A. flying   B. coming   C. running   D. returning

(   ) 4. A. ruins   B. survivals   C. relics   D. remains

(   ) 5. A. it   B. that   C. this   D. which

(   ) 6. A. at   B. on   C. over   D. beneath

(   ) 7. A. spread   B. scattered   C. distributed   D. separated

(   ) 8. A. environment   B. climate   C. temperature   D. situation

(   ) 9. A. through   B. in   C. across   D. within

(   ) 10. A. point   B. icy   C. cold   D. freezing

(   ) 11. A. vapour   B. moisture   C. wetness   D. mixture

(   ) 12. A. face   B. contact   C. meet   D. encounter

(   ) 13. A. rise   B. climb   C. raise   D. lift

(   ) 14. A. rain   B. snow   C. wind   D. rainfall

(   ) 15. A. weightily   B. forcefully   C. deeply   D. heavily

(   ) 16. A. land   B. ocean   C. forest   D. mountain

(   ) 17. A. with   B. of   C. within   D. from

(   ) 18. A. harvested   B. produced   C. created   D. invented

(   ) 19. A. Africa   B. Asia   C. Antarctica   D. America

(   ) 20. A. detected   B. found   C. disclosed   D. located

Why does cream go bad faster than butter? Some researchers think they have the answer,and it 1        down to the 2        of the food,not its chemical composition―a finding that could help 3        some processed foods of chemical preservatives (防腐剂) .

Cream and butter 4        pretty much the same substances,so why cream should sour much faster has been a mystery. Both are emulsions (孚L状液) 一tiny globules (小球体) of one liquid evenly distributed throughout another. The difference 5        in what's in the globules and what's in the surrounding liquid,says Brocklehurst,who led the 6      .

In cream,fatty globules drift 7        in a sea of water. In butter,globules of a watery solu?tion are locked away in a sea of 8.        The bacteria which make the food go bad 9        to live in the watery regions of the mixture. "This means that in cream,the bacteria are 10        to grow throughout the mixture," he says.

When the situation is 11       ,the bacteria are locked away in compartments (间隔室) bur?ied deep in the sea of fat. 12       in this way,individual colonies cannot spread and 13        run out of nutrients (养料) .They also slowly 14        themselves with their waste products. "In but?ter,you get a selflimiting system which stops the bacteria 15       ," says Brocklehurst.

The researchers are already working with food companies 16        to see if their products can be made resistant 17        bacterial attack through alterations to the food's structure. Brockle?hurst believes it will be possible to 18        the emulsions used in salad cream,for instance,more like 19        in butter. The key will be to do this while keeping the salad cream 20        and not turning it into a solid lump.

(   ) 1. A. puts   B. turns   C. takes   D. comes

(   ) 2. A. variety   B. content   C. quality   D. structure

(   ) 3. A. help   B. relieve   C. rid   D. discharge

(   ) 4. A. contain   B. include   C. cover   D. enclose

(   ) 5. A. remains   B. stays   C. shows   D. lies

(   ) 6. A. investigation   B. survey   C. exploration   D. inspection

(   ) 7. A. away   B. about   C. over   D. off

(   ) 8. A. globules   B. cream   C. fat   D. water

(   ) 9. A. wish   B. choose   C. prefer   D. decide

(   ) 10. A. free   B. likely   C. busy   D. exhausted

(   ) 11. A. opposite   B. reversed   C. returned   D. advanced

(   ) 12. A. Caught   B. Trapped   C. Seized   D. Captured

(   ) 13. A. tightly   B. slowly   C. firmly   D. rapidly

(   ) 14. A. murder   B. poison   C. pollute   D. release

(   ) 15. A. decreasing   B. changing   C. growing   D. raising

(   ) 16. A. anxious   B. keen   C. clever   D. unwilling

(   ) 17. A. in   B. of   C. on   D. to

(   ) 18. A. make   B. take   C. design   D. create

(   ) 19. A. those   B. ones   C. that   D. it

(   ) 20. A. liquid   B. vapour   C. substance   D. fresh

The "show business" attracts many young people. 1       only very few can hope to be?

come famous.

Talent is not 2        Without a good manager,a performer can never hope to succeed. Fashion is 3        important in this business. The best tailor in the world will never be successful if he makes 4        clothes. In exactly the same way,a performer must change his "act" in order to 5        the taste of the moment. This is 6        for actors and dancers,but perhaps most of all for 7       "Pop" stands for "popular",and a pop singer has to 8        to become popular. He must either give the public what they want,or he must find 9        way of singing that will at?tract their attention. 10       when he has succeeded,and his records are sold everywhere,he can not 11       . He must work harder than ever to remain popular,12       there are always younger trying to become famous. The life of a successful pop singer is 13       . He can only relax when he is alone,because everything he does is watched and reported in the special news?paper written for the "fans". The fans are the most important people in the world for 14       . They buy his record,they go to his concerts,and they make him 15       . But they can be very troublesome,too. They sometimes 16        handkerchiefs,they tear off buttons,and they even cut off pieces of the unfortunate singer's hair. Many singers have been forced to 17        A pop singer has to spend a lot of money on 18       .

because he must always look smart. He must have a nice car. And 19      ,he must al?ways keep smiling for the benefit of 20       .

(   ) 1. A. Unfortunately   B. Therefore   C. Naturally   D. Luckily

(   ) 2. A. important   B. enough   C. necessary   D. encouraged

(   ) 3. A. still   B. yet   C. even   D. also '

(   ) 4. A. beautiful   B. oldfashioned   C. new   D. strange

(   ) 5. A. follow   B. get   C. change   D. agree

(   ) 6. A. easy   B. same   C. true   D. good

(   ) 7. A. artists   B. tailors   C. women   D. singers

(   ) 8. A. act   B. work hard   C. travel   D. sing

(   ) 9. A. a new   B. an easy   C. a popular   D. a strange

(   ) 10. A. Even   B. Unless   C. If   D. But

(   ) 11. A. give up   B. leave   C. relax   D. satisfy

(   ) 12. A. so   B. then   C. because   D. and

(   ) 13. A. simple   B. very interesting

   C. exciting   D. not at all easy

(   ) 14. A. the public   B. the show business

   C. the first star   D. the singer

(   ) 15. A. satisfy   B. exalted   C. rich and famous   D. happy

(   ) 16. A. receive   B. steal   C. send   D. accept

(   ) 17. A. sing   B. give   C. hide   D. leave

(   ) 18. A. traveling   B. clothes   C. food   D. homing

(   ) 19. A. thus   B. more or less   C. after all   D. above all

(   ) 20. A. his public   B. himself   C. all   D. his manager

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