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题目列表(包括答案和解析)

In 2004,the World Health Organization,WHO,warned of a possible outbreak of another serious disease which may be even more deadly than SARS.The WHO believes that it is likely that bird flu will spread to human beings in the next few years.If it does,up to seven millions people could die from the disease.

Diseases like bird flu are caused by viruses,that is,tiny things which change and become more dangerous over time.When a new type of a common virus changes,it may be able to get past the body’s immune(免疫的)system.If that happens,humans are in great danger until a cure or treatment becomes available.

There have always been viruses and people always get sick,of course,but as we saw with SARS,the situation is more difficult today.People travel more than ever before,which means that disease can spread quickly and across large areas——in fact the whole world.

Scientists are already working on drugs that will prevent or limit the effect of a new virus,but the process takes time.It is just as important to make sure that countries,especially poor countries,are prepared to deal with the disease. New disease usually affect poor areas the most,so we must help develop health care in all countries.

The situation is more serious today because           

A.people travel more                                      B.people don’t eat healthy food

C.there aren’t enough hospitals                        D.scientists can’t find a cure

From this passage we know           

A.bird flu will surely spread to human beings in the next few years.

B.a virus changes and become less dangerous over time.

C.SARS is 1ikely to come again in some years.

D.poor areas usually suffers more from new diseases than rich areas.

The possible title of this passage is

A.The Work of WHO

B.Scientists Are Working Hard on Drugs for Diseases

C.What Is a Virus

D.Virus Changes and Causes New Diseases Over Time

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A "lost tribe" that reached America from Australia may have been the first Native Americans, according to a new theory.

If proved by DNA evidence, the theory will break long established beliefs about the southerly migration of people who entered America across the Bering Strait, found it empty and occupied it.

On this theory rests the belief of Native Americans to have been the first true Americans. They would be classified to the ranks of escapee, beaten to the New World by Aboriginals (土著人) in boats.

To a European, this may seem like an academic argument, but to Americans it is a philosophical question about identity (身份), Silvia Gonzales, of Liverpool University said .

Her claims are based on skeletons found in the California Peninsula of Mexico that have skulls (头骨) quite unlike the broad Mongolian features of Native Americans. These narrow-skulled people have more in common with southern Asians, Aboriginal Australians and people of the South Pacific Region.

The bones, stored at the National Museum of Anthropology (人类学) in Mexico City, have been carbon-dated and one is 12,700 years old, which places it several thousand years before the arrival of people from the North. "We think there were several migration waves into the Americas at different times by different human groups," Dr. Gonzales said. "The timing, route and point of origin of the first colonization of the Americas remains a most contentious topic in human evolution."

But comparisons based on skull shape are not considered conclusive by anthropologists, so a team of Mexican and British scientists, backed by the Natural Environment Research Council, has also attempted to take out DNA from the bones. Dr. Gonzales declined yesterday to say exactly what the results were, as they need to be checked, but indicated that they were consistent(一致) with an Australian origin.

It is generally considered that the first Native Americans came from _____.

       A.North Asia      B.Australia   C.South Pacific   D.South Asia

The skeletons found in the California Peninsula of Mexico have _____.

       A.the broad skull shape     

       B.the narrow skull shape

       C.different features of Aboriginal Australians   

       D.the same features of Native Americans

The underlined “contentious” is similar in meaning to “_____”.

       A.likely to cause great interest    B.difficult to solve

       C.well-known to all           D. likely to cause argument

Which of the following statements is true according to the text?

       A.Research on skulls can draw an exact conclusion.

       B.DNA tests have proved the fact that the first Native Americans came from Australian.

       C.Scientists are still not sure about the origin of the Native Americans.

       D.People began to enter America across the Bering Strait about 12,700 years ago.

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C

The United States is one of the few countries in the world that has an official day on which fathers are honored by their children.On the third Sunday in June, fathers all across the United States are given presents, treated to dinner or otherwise made to feel special.

However, the idea for creating a day for children to honor their fathers began in Spokane, Washington.A woman by the name of Sonora Smart Dodd thought of the idea for Father’s Day while listening to a Mother’s Day sermon(布道)in 1909.Having been raised by her father, Henry Jackson Smart, after her mother died, Sonora wanted her father to know how special he was to her.It was her father that made all the parental sacrifices and was, in the eyes of his daughter, a selfless and loving man.Sonora’s father was born in June, so she chose to hold the first Father’s Day celebration in Spokane, Washington on the 19th of June, 1910.

In 1924 President Calvin Coolidge declared the third Sunday in June as Father’s Day.Roses are the Father’s Day flowers: red to be worn for a living father and white if the father has died.

When children can’t visit their fathers or take them out to dinner, they send a greeting card.Traditionally, fathers prefer greeting cards that are not too sentimental(感伤的).Most greeting cards are too special so fathers laugh when they open them.Some give heartfelt thanks for being there whenever the child needed Dad.

64.The United States is special in Father’s Day because ______.

      A.many people celebrate the day           B.only America celebrates the day

      C.America makes it an official day  D.all men are honored in America

65.At first, Father’s Day was fixed on June 19th because ______.

      A.Sonora honored her father on her father’s birthday

      B.Sonora’s birthday was June 19

      C.it was decided by the president at that time

      D.her mother died on June 19

66.How many years had passed before Father’s Day became an official day since the father’s day was celebrated?

      A.4          B.10      C.14        D.24

67.According to the passage, on Father’s Day,  ______.

      A.people will wear the same flowers to honor their fathers

      B.only daughters wear red flowers to honor their fathers

      C.children must go home to honor their fathers

      D.fathers are often honored in different ways

68.According to the passage, we can infer that Henry Jackson Smart ______.

      A.was very kind to anyone       B.did a lot for his daughter

      C.was the first father honored in 1924     D.always help others by giving money

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A new study says one part of the human brain may become smaller as the result of a condition known as jet lag. Jet lag results from flying long distances in an airplane. People with jet lag may feel extremely tired for several days. They may also have problems thinking clearly and remembering.

Recently a researcher at the University of Bristol in Britain reported the findings of his jet lag study, which involved twenty young women who worked for international airlines. They had served passengers on airplanes for five years. These flight attendants flew across many countries and at least seven time zones. In the study, the flight attendants had different amounts of time to recover from jet lag. Half the women spent five days or fewer in their home areas between long flights The other half spent more than fourteen days in their home areas.

The researcher took some saliva from the women's mouths to measure levels of a hormone(荷尔蒙) that increases during stress (紧张). He tested them to see if they could remember where black spots appeared on a computer screen. And he took pictures of their brains to measure the size of the brain's temporal lobes (脑叶).

It was found that the women who had less time between flights had smaller right temporal lobes. This area of the brain deals with recognizing and remembering what is seen. The same group performed worse and had slower reaction times on the visual memory test. And their saliva samples showed higher levels of stress hormones.

The researcher believes the brain needs at least ten days to recover after a long trip. He says airline workers told him their ability to remember got worse after working on planes for about four years. Other studies have shown that increased feelings of stress can cause a loss of cells in the part of the brain that controls memory.

Scientists say more tests are needed to study the effects of jet lag on the brain. They want to find out if too much jet lag could permanently (永久性的) affect memory.

According to the text, jet lag _________.

A. can cause difficulties in speaking

B. can make people feel tired for a few weeks

C. can be only found in flight attendants

D. can be caused by flying over several time zones

It can be inferred from the text that _________.

A. the conclusion is refused by many scientists

B. scientists fear that this research is not done properly

C. every scientific conclusion needs the support from many tests

D. the women who were examined in the research were not healthy

From the result of the research we can see that _________.

A. the women who have longer rest at home show better memory

B. the women who fly in short time have smaller right temporal lobes

C. the women who have longer flights fail the memory test

D. the women who rest more than 14 days produce less hormones

What is the subject discussed in the text?

A. The cause of jet lag.      B. A story of a group of flight attendants.

C. The importance of having enough rest after flights.

D. A research about the effects of jet lag on the brain.

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A dam is a man-made structure built across a river. Most dams are built to control a river’s water flow, improve navigation and control flooding. However, some dams are built to produce hydro-electric power.

Hydro-electric power is produced as water passes through a dam, and into a river below. The more water that passes through a dam, the more energy is produced. Once a dam is built, a man-made lake is created behind the dam.

Electricity is produced by a kind of equipment called a turbine(水轮机). Turbines contain metal coils(线圈) surrounded by magnets(磁铁). When the magnets move round rapidly over the metal coils, electricity is produced. Turbines are located inside dams. The falling water makes the magnets go around the coils.

Dams provide clean energy, but they can also harm the environment. Species that use rivers to reproduce are often hurt by dams. In the Northwest of the US, the population of fishes has dropped from 16 million to 2.5 million since hydro-electric plants were built on the Columbia River. Dams all over the world have hurt some species. 

  The highest dam in the Unites States is located near Oroville, California. The Oroville Dam towers 230 meters and is more than a mile wide. This dam was built in 1968, 22 years after the Hoover Dam. The Hoover Dam, on the Nevada-Arizona border controls the Colorado river. It is 221 meters high and has 2.6 million hectare-meters of water.

The highest dam in the world is the Nurek Dam on the Vakhsh River in Tadzikistan, a country in central Asia. This dam is 300 meters tall. 

Which of the following statements is NOT true according to the passage?              

A. Some dams are built for controlling a river’s water flow.

B. Hydro-electric power is usually produced through a dam.

C. Dams can offer energy and they are harmless to the environment.

D. Generally speaking, where there is a dam, there is a man-made lake.

The third paragraph mainly tells us _____.                          

  A. how hydro-electric power is produced

  B. What a turbine is and how it works 

  C. how the magnets and the metal coils work

  D. how the falling water passes through a turbine                     

The dam which controls the Colorado river is ____.                  

A. the Oroville Dam  B. the Hoover Dam  C. the Nurek Dam  D. the Vakhsh Dam

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