单选题A peculiarly pointed chin is his most memorable facial characteristic.A. markB. featureC. traceD. appearance

单选题The expert used a picture to give out the illusation.A. lessonB. explanationC. practiceD. show

单选题{{B}}第二篇{{/B}} Pushbike Peril Low speed bicycle crashes can badly injure or even kill children if they fall onto the ends of the handlebars(车把) so a team of engineers is redesigning the humble handlebar in a bid to make it safer. Kristy Arbogast, a bioengineer at the Children's Hospital of Philadelphia in Pennsylvania, began the project with her colleagues after a study of serious abdominal(腹部的) injuries in children in the past 30 years showed that more than a third were caused by bicycle accidents. "The task was to identify how the injuries occurred and come up with some countermeasures(对策)." she says. By interviewing the children and their parents, Arbogast and her team were able to reconstruct(重建；重构) many of the accidents and identified a common mechanism responsible for serious injures. They discovered that most occur when children hit an obstacle at a slow speed, causing them to topple over. To maintain their balance they turn the handlebars through 90 degrees, but their momentum (冲力) forces them into the end of the handlebars. The bike then falls over and the other end of the handlebars hits the ground, ramming it into their abdomen. The solution the group came up with is a handgrip(握柄) fitted with a spring and damping(制动的；减速的，缓冲的) system. The spring absorbs up to 50 per cent of the forces transmitted through the handlebars in an impact. The group hopes to commercialize(使商品化) the device, which should add only a few dollars to the cost of a bike. "But our task has been one of education because up until now, bicycle manufacturer were unaware of the problem. " says Arbogast. The team has also approached the US Consumer Product Safety Commission to try to persuade manufacturers to adopt the new design. A decision is expected later this year.

单选题{{B}}第二篇{{/B}} Explorer of the Extreme Deep Oceans cover more than two-thirds of our planet. Yet, just a small fraction of the underwater world has been explored. Now, Scientists at the Woods Hole Oceanographic Institution (WHOI) in Massachusetts are building an underwater vehicle hat will carry explorers as deep as 6,500 meters (21,320 feet). The new machine, known as a manned submersible or human-operated vehicle (HOV), will replace another one named Alvin which has an amazing record of discovery, playing a key role in various important and famous undersea expeditions. Alvin has been operating for 40 years but can go down only 4,500 meters (14,784 feet). It's about time for an upgrade ,WHOI researchers say. Alvin was launched in 1964. Since then, Alvin has worked between 200 and 250 days a year, says Daniel Fornari, a marine geologist and director Of the Deep Ocean Exploration Institute at WHOI. During its lifetime, Alvin has carried some 12,000 people on a total of more than 3,000 dives. A newer, better versions of Alvin is bound to reveal even more surprises about a world that is still full of mysteries, Fornari says. It might also make the job of exploration a little easier. "We take so much for granted on land. " Fomari says. "We can walk around and see with our eyes how big things are. We can see colors, special arrangements. " Size-wise, the new HOV will be similar to Alvin. It'll be about 37 feet long. The setting area inside will be a small sphere, about 8 feet wide, like Alvin. It'll carry a pilot and two passengers. It will be just as maneuverable. In most other ways, it will give passengers more opportunities to enjoy the view, for one thing. Alvin has only three windows, the new vehicle will have five, with more overlap so that the passengers and the pilot can see the same thing. Alvin can go up and down at a rate of 30 meters every second, and its maximum speed is 2 knots (about 2.3 miles per hour), while the new vehicle will be able to ascend and descend at 44 meters per second. It'll reach speeds of 3 knots, or 3.5 miles per hour.

单选题The leader"s corruption undermined the image of the company.

单选题The Book of Life So far, scientists have named about 1.8 million living species (特种), and that's just a small part of what probably exists on Earth. With so many plants, animals, and other creatures covering the planet, it can be tough to figure out what type of spider is moving up your leg or what kind of bird is flying by. A soon-to-be-launched Web site might help. An international team of researchers has announced the creation of a Web-based Encyclopedia (百科全书) of Life (EoL). The project aims to catalog every species on Earth in a single, easy-to-use reference guide. To get the encyclopedia started, the creators will use information from scientific databases (数据库) that already exist. And eventually, in special sections of the site, non-scientists with specialized (专门的) knowledge will get to join in. Bird-watchers, for example, will be able to input which birds they've seen and where. The technology for this kind of tool has only recently become available. As the EoL develops, you might find it useful for school projects. The site will feature special pa ges for kids who are studying ecosystems (生态系统) in their neighborhoods. To make sure the encyclopedia is accurate, scientists will review much of the information added to it. People who visit the site will be able to choose to leave out pages that haven't been reviewed. Another convenient feature of the EoL is that you'll be able to pick the level of detail you see to match your interests, age, and current knowledge. If you wanted to learn about bears for a science class report, for example, you could use the "novice " setting to get basic information about the animals. On the "expert" setting, on the other hand, you could get much more detailed information about the history, literature, and exploration of bears. It now takes years for scientists to collect all the data they need to describe and analyze species. The creators of the Encyclopedia of Life hope that their new tool will speed that process.

单选题The indecisive man was readily persuaded to change his mind again.

单选题A．notably short man, he plays basketball with his staff several times a week. A．practically B．considerably C．remarkably D．fairly

单选题Magaplane (巨型飞机) The Boeing Corp. and Europe's Airbus consortium (财团) are preparing to offer bigger airplanes to the world's airlines. Now that talks on a joint project have broken down, Boeing is pushing a stretched (拓展的) version of 747, and Airbus is designing an all-new aircraft, known as the A3XX. Seating 550 passengers in the basic model, and 650 in a stretched version, the 1.2 million pound A3XX will not only be the largest airplane in the world, but it will also be one of the most advanced. The outer wings and the horizontal stabilizer (as big as a smaller jet's wing) will be made of carbon-fiber composite materials, and will be the largest such structures on any aircraft except the B-2 stealth bomber (隐形轰炸机). Metal skins will be welded (焊接) together with lasers, removing thousands of fasteners. When a strong wind strikes the A3XX's 260-foot wing, movable control surfaces will prevent it from flexing (扭曲) like a giant spring. This will make the ride smoother and will save weight by reducing the load on the wing spars (翼梁). A flexible-skinned flap (副翼) will subtly change the wing's curvature (曲面) to match the airplane's changing weight as it burns fuel on each journey. The A3XX will carry up to 1,600 meals, filling more than 100 food and beverage (饮料) carts. To make more room for passengers, Airbus plans to put the carts in the lower hold; automatic conveyors and elevators will deliver them to the two passenger decks. Airlines have asked Airbus to look at extra features ranging from lower-deck sleeper cabins to a children's playroom.

单选题It is reasonable to accept his plan.A. usefulB. sensibleC. practicalD. feasible

单选题Her faith upheld her in times of sadness.

单选题Shopping habits in the United States have changed greatly in the last quarter of the 20th century. As early as in the 1900s most American towns and cities had a Main Street. Main Street was always in the heart of a town. This street was (51) on both sides with many varied businesses. Here, shoppers walked into stores to look at all sorts of merchandise: clothing, furniture, hardware, groceries. (52) , some shops offered service. These shops included drugstores, restaurants, shoe repair stores, and barber or hairdressing shops. (53) in the 1950s, a change began to take place. Too many automobiles had crowded into Main Street (54) too few parking places were (55) shoppers. Because the streets were crowded, merchants began to look with interest at the open spaces (56) the city limits. Open space is what their car driving customers needed. And open space is what they got (57) the first shopping centre was built. Shopping centres, or rather malls, (58) as a collection of small new stores (59) crowded city centres. (60) by hundreds of free parking space, customers were drawn away from (61) areas to outlying malls. And the growing (62) of shopping centres led (63) to the building of bigger and better stocked stores. (64) the late 1970s, many shopping malls had almost developed into small cities themselves. In addition to providing the convenience of one stop shopping, malls were transformed into landscaped parks, (65) benches, fountains, and outdoor entertainment.

单选题Because of Oden's uniqueness, he is always performing in the spotlight and subject to public Uscrutiny/U.

单选题You should cultivate the habit of reading carefully.

单选题People have been painting pictures for at least 30,000 years. The earliest pictures were painted by people who hunted animals. They used to paint pictures of the animals they wanted to catch and kill. Pictures of this kind have been found on the walls of caves in France and Spain. No one knows -why they Were painted there. Perhaps the painters thought that their pictures would help them to catch these animals. Or perhaps human beings have always wanted to tell stories in pictures. About 5000 years ago, the Egyptians and other people in the Near East began to use pictures as kind of writing. They drew simple pictures or signs to represent things and ideas, and also to represent the sounds of their language. The signs there people used became a kind of alphabet. The Egyptians used to record information and to tell stories by putting picture-writing and pictures together. When an important person died, scenes and stories from his life were painted and carved on the walls of the place where he was buried. Some of these pictures are like modem comic strip stories. It has been said that Egypt is the home of the comic strip. But for Egyptians, pictures still had magic power. So they did not try to make their way of writing simple. The ordinary people could not understand it. By the year 1000 BC, people who lived in the area around the Mediterranean Sea had developed a simpler system of writing. The signs they used were very easy to write, and there were fewer of them than in the Egyptian system. This was because each sign, or letter, represented only one sound in their language. The Greeks developed this system and formed the letters of the Greek alphabet. The Romans copied the idea and the Roman alphebet is now used all over the world. These days, we can write down a story, or record information, without using pictures. But we still need pictures of all kinds: drawing, photographs, signs and diagrams. We find them everywhere: in books and newspapers, in the street, and on the wails of the places where we live and work. Pictures help us to understand and remember things more easily, and they can make a story much more interesting.

单选题A Biological Clock Every living thing has what scientists call a biological clock that controls behavior. The biological clock tells 1 when to form flowers and when the flowers should open. It tells 2 when to leave the protective cocoons and fly away, and it tells animals and human beings when to eat, sleep and wake. Events outside the plant and animal 3 the actions of some biological clocks. Scientists recently found, for example, that a tiny animal changes the color of its fur 4 the number of hours of daylight. In the short 5 of winter, its fur becomes white. The fur becomes gray brown in color in the longer hours of daylight in summer. Inner signals control other biological clocks. German scientists found that some kind of internal clock seems to order birds to begin their long migration 6 twice each year. Birds 7 flying become restless when it is time for the trip, 8 they become calm again when the time of the flight has ended. Scientists say they are beginning to learn which 9 of the brain contain biological clocks. An American researcher, Martin Moorhead, said a small group of cells near the front of the brain 10 to control the timing of some of our actions. These 11 tell a person when to 12 , when to sleep and when to seek food. Scientists say there probably are other biological clock cells that control other body activities. Dr. Moorhead is studying 13 our biological clocks affect the way we do our work. For example, most of us have great difficulty if we must often change to different work hours. 14 can take many days for a human body to accept the major change in work hours. Dr. Moorhead said industrial officials should have a better understanding of biological clocks and how they affect workers. He said 15 understanding could cut sickness and accidents at work and would help increase a factory"s production.

单选题The mail I wrote to my mom was delivered this morning.

单选题Technological Utopia for Developing Countries Cyberspace (网络空间), data superhighways, multimedia for those who have seen the future, the linking of computers, television and telephones will change our lives forever. Yet for all the talk of a forthcoming technological Utopia (乌托邦) ,little attention has been given to the implications of these developments for the poor. As with all new high technology, while the West concerns itself with the "how", the question of "for whom" is put aside once again. Economists are only now realizing the full extent to which the communications revolution has affected the world economy. Information technology allows the extension of trade across geographical and industrial boundaries, and transnational corporations take full advantage of it. Terms of trade exchange, interest rates and money movements are more important than the production of goods. The electronic economy made possible by information technology allows the haves to increase their control on global markets with destructive impact on the have-nots. For them the result is instability. Developing countries which rely on the production of a small range of goods for export are made to feel like small parts in the international economic machine. As "futures" (期货) are traded on computer screens, developing countries simply have less and less control of their destinies. So what are the options for regaining control? One alternative is for developing countries to buy in the latest computers and telecommunications themselves—so-called "development communications" modernization. Yet this leads to long-term dependency and perhaps permanent constraints on developing countries" economies. Communications technology is generally exported from the U.S., Europe or Japan; the patents, skills and ability to manufacture remain in the hands of a few industrialized countries. It is also expensive, and imported products and services must therefore be bought on credit—credit usually provided by the very countries whose companies stand to gain. Furthermore, when new technology is introduced there is often too low a level of expertise to exploit it for native development. This means that while local elites, foreign communities and subsidiaries of transnational corporations may benefit, but not developing countries.

单选题For years, U. S. automakers have fought tougher regulations by arguing that Americans tend to prefer larger, gas-guzzling SUVs and trucks. That's not always true: when gas prices were at an all-time high last summer, sales of SUVs were down considerably, while hybrids flew off dealer lots. Since then, prices at the pump have dropped-and so has the appetite for small cars. As long as the price of gas remains volatile(易变的, 动荡不定的), it's far from certain that Americans will buy the more efficient cars and trucks the new standards will require automakers to produce. In the long run, though, a gas tax that puts a floor on fuel prices may be the only way to break America's SUV addiction. But Obama has said he's not interested. "You need a price signal. Regulations alone won't do it," says Lester Lave, director of the Carnegie Mellon Green Design Initiative. Americans' appetite for SUVs dropped whenA. gas prices hit new high last summer.B. hybrids were out of stock last summer.C. the government set limits on fuel price last summer.D. the gas price remained fluctuing last summer.

单选题Jack was dismissed .