题目内容

    It is midnight on September 22, 2012. The sky above Manhattan,New York is filled with a curtain of colorful light. New Yorkers are fascinated by the beautiful aurora (极光). However, their fascination is short-lived.

    Within a few seconds, electric bulbs dim and flicker (闪烁), then become unusually bright for a few seconds. Then all the lights go out. Within 90 seconds, the entire eastern half of the US is without power.

          Besides the US, Europe, Japan and China are also hit by the same terrible event. It is a violent solar flare (太阳耀斑) ,150 million kilometers away on the surface of the sun.

          Science fiction? No. A report funded by NASA and issued by the US National Academy of Sciences in January this year says it could happen.

    A massive solar flare is most likely on a spring or autumn night in 2012, according to the report.

    Solar flares are huge explosions on the surface of the sun. In a matter of just a few minutes they heat material to many millions of degrees and release as much energy as a billion megatons (百万吨) of TNT explosives. Solar flares release a stream of charged high-energy particles (粒子). They are called “solar winds”.

    If one solar “wind” should hit the Earth’s magnetic shield (磁场), the result could be terrible for humans.

    But there’s no need to run for cover from solar winds. They do not harm life on Earth, they only affect the way we live, especially since we depend so much on modern technology. They can pump extra electricity into power lines and pipelines, causing blackouts and fuel leaks. Solar winds are also known to affect mobile phone operations and may disrupt wireless Internet services.

    Moreover, solar winds can prevent normal satellite operations, and disrupt radio communications and navigation systems such as the Global Positioning System.

    Auroras are powered by solar wind. This wind blows past the Earth at about 400-700 km per second and creates storms in the Earth’s magnetic environment. In the polar regions these explode into southern or northern polar lights.

    The most serious solar storm that hit Earth in history happened in 1859. It caused the failure of telegraph systems in Europe and North America.

    So, for humans, the sun is a double-edged sword. Without the sun, there would be no life on Earth. Without the sun, Earth would be a frozen dark ball floating in space. However, on the other hand, the sun can disorder our lives from time to time.

56. What is the main idea of the passage?

         A. It introduces to readers the advantages and disadvantages of the sun.

         B. It describes a science fiction set in Manhattan on 22 September 2012.

         C. It shows readers the way in which solar winds form inside the sun.

         D. It explains what solar flares are and their effects on human life.

57. The first two paragraphs are written ____.

         A. to show a beautiful scene in a true story

         B. to describe the beautiful scenery of Manhattan

         C. to describe the power problem around the world

         D. to introduce the topic of this passage

58. What can we conclude from the passage?

         A. Solar flares will do great harm to those who are using the Internet.

         B. Solar flares cannot reach as far as the polar regions.

         C. Solar flares are huge explosions that happen inside the sun.

         D. But for our reliance on technology, solar flares wouldn’t

affect us so much.

59. Solar winds will likely affect us in the following ways EXCEPT that ____.

         A. normal satellite operations will be stopped

         B. the lights in the areas affected will go out at the same time

         C. people on the streets will be struck to death

         D. some navigation systems will be out of order

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British researchers are looking for volunteers willing to eat a piece of chocolate daily for a year in the name of science. The trial(实验) will explore whether flavonoids (类黄酮) found in chocolate and other foods can reduce the risk of heart disease.

“We are looking at a high risk group first,” said Aedin Cassidy, a biochemist who will lead the study.

Previous studies have suggested dark chocolate is rich in the beneficial flavonoids linked with heart health, but experts note the high sugar and fat content of most commercially available chocolate might cancel out some of the advantages. Other research has also shown dark chocolate appears to lower blood pressure, improve the function of blood vessels (血管)and reduce the risk of heart attack.

This has encouraged companies to market specific products containing dark chocolate. Mars Inc has introduced Cocoa Via, a line of dark and premium chocolates that plays up such health advantages.

Cassidy said her team will also publish findings in the American Journal of Clinical Nutrition showing that flavonoids found in soy and cocoa appear to have the strongest effects of reducing risk of heart disease.

The next step will organize 150 women volunteers with a specific illness. The researchers will look at whether flavonoids help reduce blood pressure, cut cholesterol levels and improve the condition of blood vessels.

Half the women in the year-long study will eat chocolate containing 30 grams of flavonoids found in soy, cocoa and other fruits and vegetables. The others will get chocolate without the active flavonoids.

“This could help doctors give advice to patients on the type and amount of foods to eat to reduce heart disease risk—and it does not necessarily need to be chocolate,” Cassidy said. “If this trial works we will be able to advise on a whole range of foods. People won't have to go around eating specially designed chocolate.”

1. What is the best title for the passage?

A. Volunteers wanted for chocolate study.           B. Chocolate is good for health.

C. A new research on heart attacks.                  D. Flavonoids found in chocolate.

2. What’s the purpose of the trial?

A. To test the advantages of a new kind of chocolate.

B. To find cures for heart disease.

C. To discover how to control blood pressure.

D. To explore the advantages of flavonoids.

3. From Paragraph 3 we can infer that __________.

A. Cassidy’s team has done several studies on chocolate

B. dark chocolate has proved beneficial to health

C. people should eat much chocolate with high sugar and fat

D. most commercially available chocolate doesn’t contain flavonoids

4. Which of the following statements is TRUE according to the passage?

A. All the volunteers will eat the same chocolate.

B. CocoaVia is a company that produces dark chocolate.

C. People who want to take part in the trial should be healthy.

D. Soy, cocoa, some fruit and vegetables contain flavonoids.

The Harvard Student-led Walking Tour

Let a student show you Harvard···on a free walking tour.

   We welcome our neighhours to stop by the Harvard University Events&Information Centre, located in the Holyoke Centre Arcade at 1350 Massachusetts Avenue in the heart of Harvard Square in Cambridge.

   Let a student take you and your family, school,or organization on an engaging,hour-long free historical tour of the Harvard Campus. The tours leave from the Events&Infomlation Centre.Not only will you discover the location of fascinating exhibition and programmers on campus, you will also see Harvard’s rich sampling of American history and architecture from the Colonial period to the present.

Sehedule of Tours

    Tours leave the Events&Information Centre at 10 a.m. and 2 p.m. Monday through Friday, and at 2 p.m. on Saturday through the academic year (February 4 through May 2;September 23 through December 16). Summer tours (June 24 through August 15) are offered at 10 a.m., 11:15a.m.,2 p.m.,and 3:15 p.m. Monday through Saturday.Reservations for special tours of 20 or more people may be made by calling the Events&Information Centre at (617) 495—1573 or emailing icenter@ camail. harvard,edu.Tours are suspended March 23 through April 2 for Spring Break, May 3 through June 23 for Spring intercession(祷告),and August 16 through September 22 for Summer intercession.

    NOTE:Prospective(未来的)students may take tours originating at the Harvard Admission office, located at Byerly Hall on 8 Garden Street in Cambridge.From April through August,the Admissions staff conducts an information session at l0 a. m.,followed by an 11 a. m. tour.Monday through Friday On Saturdays.there is no information session but the 11 a.m.tour is still scheduled.Another session is held year round at 2 p. m. with a 3 p. m. tour following.For more information on tours for prospective students,please call at(617)495—1551.

Harvard University Events&Information Centre

Location:Holyoke Centre Arcade.1350 Massachusetts Avenue,Cambridge MA 02138

Phone:(617)495—1573

68. A person can join in a tour at ________ on Saturday through the academic year.

    A. 10 a.m.      B. 2 p.m.      C. 11:15 a.m.    D. 3:15 p.m.

69. If you want to go for an information session, you can go on _________.

    A. May 2       B. June 23     C. August 20    D. September 1

70. A student who wants an information session may _______ for more information.

    A. call(617)495—1573               B. call(617)495—1551

    C. email icenter@ camail. harvard, edu  D. go to the Events&Information Centre

71. The above advertisement is mainly intended for ____________.

    A. foreign visitors                  B. freshmen

    C. high school students              D. those living near Harvard University

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