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Monarch without a KingdomThis November, a hundred million butterflies will drop from the sky over Mexico, like autumn leaves. But for how long Genetically modified maize (玉米) could mean extinction for this beautiful butterfly, Rafael Ruiz reports.Although its body is about 3 cm long and it only weighs 1 gm, the Monarch butterfly manages to travel 5,000 km each year. It seems to be so fragile, but its long journeys are proof of its amazing ability to survive. This autumn, the Monarch butterfly will once more set out on its journey from the U.S. It will keep going until it reaches Mexico. It travels these huge distances to escape the cold weather in the north.In November, millions of Monarchs fall like bright, golden rain onto the forests in the mountains of central Mexico. In the silence of these mountains you can hear a strange flapping (拍动) of wings, as the Monarchs arrive at their destination. In the mountains, which reach a height of 3,000 meters, the butterflies are safe.Before reaching their journey"s end they have faced strong winds, rain and snowstorms and they do not all manage to reach their destination. When the winters are really bad, perhaps 70 per cent of them will not survive. Their long journey to Mexico is thought to be one of the most amazing events in the whole of the American continent. When they get there they will stay until the beginning of April, when their internal calendar tells them that it is time to go back. The long journey, with all its dangers, begins again.These delicate creatures now face danger of another kind—from scientific progress. In the U.S., millions of farms grow genetically modified maize which is pure poison for the butterfly. Laboratory experiments have shown that half of the butterflies which feed on the leaves of genetically modified maize die within 48 hours. Not all experts agree that this variety of maize is responsible for the threat to the Monarchs. In spite of these doubts, the European Union has refused to approve new crops of genetically modified maize until further investigations have been carried out.Greenpeace is campaigning against genetically modified products (in Spain, there are already 20,000 hectares of modified maize). The environmental organization recently published a list of 100 species of butterfly in Europe alone which are threatened with extinction. The Mexicans like butterflies very much.
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TransportationFor many years in the desert, camels used to be the only form of transportation (运输). Before the age of modern trains, camel trains were used to carry all the goods for trading between Central Africa and Europe. Traders sometimes put together camel trains with 10,000 to 15,000 animals. Each animal often carried as much as 400 pounds and could travel twenty miles a day. This form of transportation used to be so important that camels were called "ships of the desert".Now modern trains travel across the desert in a very short time. One engine can pull as much weight as 135,000 camels. In addition, trains use special cars (车厢) for their load. Refrigerator cars carry food; boxcars (棚车) carry heavy goods; stock cars carry animals; and tank cars carry oil.Air travel is also a modern means of transportation, but it has changed since the early 20th century. The earliest planes were biplanes (双翼飞机), with two sets of wings. The top speed of this plane was 60 miles per hour. The pilots used to sit or lie on the wings in the open air. The plane engines sometimes stopped in the middle of a trip. It used to be impossible to fly in bad weather. In snow or in rain, the wings frequently became icy. Then the plane might go down.Mechanical improvements during the First World War changed airplanes. Monoplanes (单翼飞机) took the place of biplanes. Pilots flew inside of covered cabins. Still, even these planes were small and expensive. Only rich people used to be able to travel in airplanes.Now modern jets make air travel possible for all people. No place in the world is more than 24 hours away by jet. Further improvements have lowered the cost of flying, and they have made air travel much safer than it used to be. A modern 707 can carry 170 people and can fly at 600 miles per hour. People never used to eat, sleep, or watch movies on airplanes. Now these things are a normal part of air travel. Which of the following about the advantages of a train is NOT mentioned in Paragraph 2
I"ll Be Bach1 Composer David Cope is the inventor of a computer program that writes original works of classical music. It took Cope 30 years to develop the software. Now most people can"t tell the difference between music by the famous German composer J.S. Bach (1685-1750) and the Bach-like compositions from Cope"s computer.2 It all started in 1980 in the United States, when Cope was trying to write an opera. He was having trouble thinking of new melodies, so he wrote a computer program to create the melodies. At first this music was not easy to listen to. What did Cope do He began to rethink how human beings compose music. He realized that composers" brains work like big databases. First, they take in all the music that they have ever heard. Then they take out the music that they dislike. Finally, they make new music from what is left. According to Cope, only the great composers are able to create the database accurately, remember it, and form new musical patterns from it.3 Cope built a huge database of existing music. He began with hundreds of works by Bach. The software analyzed the data: it broke it down into smaller pieces and looked for patterns. It then combined the pieces into new patterns. Before long, the program could compose short Bach-like works. They weren"t good, but it was a start.4 Cope knew he had more work to do—he had a whole opera to write. He continued to improve the software. Soon it could analyze more complex music. He also added many other composers, including his own work, to the database.5 A few years later, Cope"s computer program, called "Emmy", was ready to help him with his opera, The process required a lot of collaboration between the composer and Emmy. Cope listened to the computer"s musical ideas and used the ones that he liked. With Emmy, the opera took only two weeks to finish. It was called Cradle Falling, and it was a great success! Cope received some of the best reviews of his career, but no one knew exactly how he had composed the work.6 Since that first opera, Emmy has written thousands of compositions. Cope still gives Emmy feedback on what he likes and doesn"t like of her music, but she is doing most of the hard work of composing these days! Paragraph 2 ______ A. Progress of producing music by the program B. Importance of the program C. Improvement of the program D. Why was the program invented E. Bach"s works" beauty F. An opera made by "Emmy"
TransportationFor many years in the desert, camels used to be the only form of transportation (运输). Before the age of modern trains, camel trains were used to carry all the goods for trading between Central Africa and Europe. Traders sometimes put together camel trains with 10,000 to 15,000 animals. Each animal often carried as much as 400 pounds and could travel twenty miles a day. This form of transportation used to be so important that camels were called "ships of the desert".Now modern trains travel across the desert in a very short time. One engine can pull as much weight as 135,000 camels. In addition, trains use special cars (车厢) for their load. Refrigerator cars carry food; boxcars (棚车) carry heavy goods; stock cars carry animals; and tank cars carry oil.Air travel is also a modern means of transportation, but it has changed since the early 20th century. The earliest planes were biplanes (双翼飞机), with two sets of wings. The top speed of this plane was 60 miles per hour. The pilots used to sit or lie on the wings in the open air. The plane engines sometimes stopped in the middle of a trip. It used to be impossible to fly in bad weather. In snow or in rain, the wings frequently became icy. Then the plane might go down.Mechanical improvements during the First World War changed airplanes. Monoplanes (单翼飞机) took the place of biplanes. Pilots flew inside of covered cabins. Still, even these planes were small and expensive. Only rich people used to be able to travel in airplanes.Now modern jets make air travel possible for all people. No place in the world is more than 24 hours away by jet. Further improvements have lowered the cost of flying, and they have made air travel much safer than it used to be. A modern 707 can carry 170 people and can fly at 600 miles per hour. People never used to eat, sleep, or watch movies on airplanes. Now these things are a normal part of air travel. According to the passage, why were camels called "ships of the desert"
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