阅读下列短文, 从所给的四个选项中, 选出最佳答案。

　　

    Dr Ungar trained rats to prefer lighted boxes. He shocked any rat　　 who went into a dark area. After five to eight days the rats learned　　 that a more peaceful life could be lived in lighted boxes. Then he　　 killed the rats. He injected (注射) parts of their trained brains into　　 638 mice who had shown they liked the dark. He put parts of the brains　　 of untrained rats into 132 other mice. These mice also liked the dark.

　　

    Animals that got the trained brains spent an average (平均) of 63　　 seconds in the dark and those that got the untrained brains averaged　　 118 seconds.

　　

(1)From the passage, we know that the rats__________.　　    

  A. like the dark　　　　　　   B. like the light 　　   

  C. are hard to be trained　　  D. are easy to be kept 

(2) How did Dr Ungar make his rats love the light?　　　　　　 

 

(3)What happened to the rats that got the trained brains?　　

  A. They spent more time in the dark.    

  B. They spent less time in the dark.    

  C. They didn't stay in the dark any longer.

  D. hey acted in their usual way. 

(4) Dr Ungar injected parts of the rats' trained brains to 638 mice to    see___________________.　　　　　　　　　　　　　　　　　　  
   A. how long they could live   
   B. where they would stay 　　
   C. what they would look like 　　
   D. if he could change their action physically 

(5)The passage doesn't tell us _______________.　　　　 

 A. whether Dr Ungar's experiment was successful or not    

 B. which animals stayed longer in the dark    

 C. how long Dr Ungar had done his experiment    

 D. when the rats realized where their good places were

The “balance of nature”is not an empty phrase. Nature provides a population to occupy a suitable environment and cuts down surplus population to fit the available food supply. One means of reducing surplus population is predators; others are parasitic diseases. Also, population density produces nervous disorders and even drives animals to mass migrations(移民群),like the lemmings of Norway who plunge（冲入）into the sea.

That predatory population increase to control other animals has long been known. Many years ago, the Hudson’s Bay Company records revealed that the fox population went up and down about a year after rabbit population had gone up and down.

Sometimes a situation occurs in which the predatory population is reduced to a level below which nature can readily replace. On Valcour Island in Lake Champlain, a costly campaign resulted in the elimination（消除）of predatory animals only to have birds and small animals increase for four years afterward. Then, lacking predator control, nature resorted to disease to cut down these populations.

Jamaica had an example of nature’s persistence in providing animals for existing habits. Sugar planters, about 75 years ago, imported mongooses（狐猴）to control rats. The mongooses killed off the rats, kids, puppies, and wildlife. Eventually, food became scarce and the mongoose’s population declines.

1. The fact that the number of predators has much to do with that of other animals 　　  .

A. is not recent knowledge　　　　　　　　　　　　　　    B.has just been learned

C.hasn’t been proved yet　　　　　　　　　　　　　　　　　　　　  D.is not important now

2. When predator control fails, nature brings animal population into balance by       .

A. eliminating the number of predators

B.seeking the help of disease to reduce other animals

C.increasing the number of other animals

D.replacing the number of predators immediately

3. When the mongooses killed off the rats they 　　  .

A. became problems themselves　　　　　　　　　　　　 B.ate the sugar crop

C.attacked humans　　　　　　　　　　　　　　　　　　　　   D.had nothing to eat

4. It is implied in this passage that 　　  .

A. sugar planter imported mongooses to control rats

B.man should never kill animals

C.man has complete control over nature

D.to upset the balance of nature can be troublesome

 

阅读理解

　　Malls are popular places for Americans to go to. Some people spend so much time at malls that they are called “mall rats”. Mall rats “shop until they drop” in hundreds of stores under one roof.

　　People like malls for many reasons. They feel safe because malls have police stations or private security guards. Parking is usually free, and the weather inside is always fine. The newest malls have beautiful rest areas with waterfalls and large green trees.

　　The largest mall in the United States is the Mall of America in Minnesota．It covers 4.2 million square feet. It has 350 stores, eight night clubs, and a seven-acre park! There are parking spaces for 12,750 cars. About 750,000 people shop there every week.

　　The first indoor mall in the United States was built in 1965 in Edina, Minnesota．People loved doing all their shopping in one place. More malls were built all over the country. Now, malls are like town centres where people come to do many things. They shop, of course. They also eat in food courts that have food from all over the world．They see movies at theatres. Some people even get their daily exercise by doing the new sport of “mall walking”. Others go to malls to meet friends.

　　In some malls, people can see a doctor or a dentist and even attend church. In other words, people can do just about everything in malls. Now residents can actually live in their favourite shopping centre.

(1)Malls are ________.

[　　]

A．large shopping centres which also act as town centres

B．large parks with shops

C．the most popular places American go to

D．town centres

(2)Why have malls become so popular?

[　　]

A．Because people can do everything there.

B．Because people can do many other things besides shopping for all they need．

C．Because people feel safe in malls with police stations around．

D．Because people enjoy the fresh air and can have a good rest there.

(3)Malls have to be large places because ________.

[　　]

A．many people drive their cars to go to malls

B．there have to be some restaurants, clinics and theatres

C．many people hope to do sports in the malls

D．they have to meet different needs for many people

(4)In doing “mall walking” people ________.

[　　]

A．shop until they drop

B．do just about everything

C．walk around the mall as a kind of exercise

D．see movies at theatres

The “balance of nature”is not an empty phrase. Nature provides a population to occupy a suitable environment and cuts down surplus population to fit the available food supply. One means of reducing surplus population is predators; others are parasitic diseases. Also, population density produces nervous disorders and even drives animals to mass migrations(移民群),like the lemmings of Norway who plunge（冲入）into the sea.

That predatory population increase to control other animals has long been known. Many years ago, the Hudson’s Bay Company records revealed that the fox population went up and down about a year after rabbit population had gone up and down.

Sometimes a situation occurs in which the predatory population is reduced to a level below which nature can readily replace. On Valcour Island in Lake Champlain, a costly campaign resulted in the elimination（消除）of predatory animals only to have birds and small animals increase for four years afterward. Then, lacking predator control, nature resorted to disease to cut down these populations.

Jamaica had an example of nature’s persistence in providing animals for existing habits. Sugar planters, about 75 years ago, imported mongooses（狐猴）to control rats. The mongooses killed off the rats, kids, puppies, and wildlife. Eventually, food became scarce and the mongoose’s population declines.

1. The fact that the number of predators has much to do with that of other animals 　　  .

A. is not recent knowledge　　　　　　　　　　　　　　    B.has just been learned

C.hasn’t been proved yet　　　　　　　　　　　　　　　　　　　　  D.is not important now

2. When predator control fails, nature brings animal population into balance by       .

A. eliminating the number of predators

B.seeking the help of disease to reduce other animals

C.increasing the number of other animals

D.replacing the number of predators immediately

3. When the mongooses killed off the rats they 　　  .

A. became problems themselves　　　　　　　　　　　　 B.ate the sugar crop

C.attacked humans　　　　　　　　　　　　　　　　　　　　   D.had nothing to eat

4. It is implied in this passage that 　　  .

A. sugar planter imported mongooses to control rats

B.man should never kill animals

C.man has complete control over nature

D.to upset the balance of nature can be troublesome

 

Holding a cell phone against your ear or stalling it in your pocket may be hazardous to your health．

       This paraphrases a warning that cell phone; manufacturers include in the small print that is often tossed aside when a new phone is purchased．Apple, for example, doesn't want iP hones to come closer to you than 1．5 centimeters; Research In Motion, Blackberry's manufacturer, recommends 2.5 centimeters．

       If health issues arise from cell phone use, the implications are huge．Voice calls - Americans chat on cell phones 2．26 trillion minutes annually - generate $109 billion for the wireless carriers．

       Devra Davis, an epidemiologist who has worked for the University of Pittsburgh, has published a book about cell phone radiation, "Disconnect." The book surveys scientific research and concludes the question is not settled.

　　Brain cancer is a concern that Ms. Davis examines. Over all, there has not been an increase in its incidence since cell phones arrived. But the average masks an increase in brain cancer in the 20-to-29 age group and a drop for the older population.

　　"Most cancers have multiple causes," she says, but she points to laboratory research that suggests low-energy radiation could damage cells that could possibly lead to cancer.

　　Children are more vulnerable to radiation than adults, Ms. Davis and other scientists point out. Radiation that penetrates only five centimeters into the brain of an adult will reach much deeper into the brains of children because their skulls are thinner and their brains contain more absorptive fluid. No studies have yet been completed on cell phone radiation and children, she says.

　　Henry Lai, a research professor in the bioengineering department at the University of Washington, began laboratory radiation studies in 1980 and found that rats exposed to radiofrequency radiation had damaged DNA in their brains.

　　Ms. Davis recommends using wired headsets or the phone's speaker. Children should text rather than call, she said, and pregnant women should keep phones away from the abdomen.

We can infer from the passage that________．

       A．Cell phone may do harm to our health if we hold it against our ear or store in our pocket

       B．Devra Davis thinks that there are many factors contributing to cancer．

       C．The increase in brain cancer in the young adults may have something to do with cell phone

       D．Children are more likely to be affected by radiation

According to the passage, how could children avoid being hurt by cell phone radiation?

       A．They can keep cell phones away from the abdomen．

       B．They can send short massage instead of making phone calls directly．

       C．They can pay more attention to the small print on the phone．

       D．They should use more advanced cell phones．

From this passage we can learn that．________．

       A．American cell phone manufacturers did not give any warning to their customers

       B．American cell phone manufacturers benefit greatly from their products

       C．Scientists have found the connection between brain cancer and ceil phone

       D．Cell phone should be banned because of the increase in brain cancer

In which column can we most probably read this passage?

       A．Advanced technology．       B．Entertainment．

       C．Science and life．            D．Celebrity．