单选题The soldier (displayed) remarkable courage in the battle．

单选题The central government is {{U}}arguing{{/U}} the education laws.

单选题In his two-hour-long lecture he made an exhaustive analysis of the issue. A. extremely thorough B. long and boring C. superficial D. unconvincing

单选题Batteries Built by Viruses What do chicken pox, the common cold, the flu, and AIDS have in common? They're all disease caused by viruses, tiny microorganisms that can pass from person to person. It's no wonder that when most people think about viruses, finding ways to steer clear of viruses is what's on people's minds. Not everyone runs from the tiny disease carders, though. In Cambridge, Massachusetts, scientists have discovered that some viruses can be helpful in an unusual way. They are putting viruses to work, teaching them to build some of the world's smallest rechargeable batteries. Viruses and batteries may seem like an unusual pair, but they're not so strange for engineer Angela Belcher, who first came up with the idea. At the Massachusetts Institute of Technology (MIT) in Cambridge, she and her collaborators bring together different areas of science in new ways. In the case of the virus-built batteries, the scientists combine what they know about biology, technology and production techniques. Belcher's team includes Paula Hammond, who helps put together the tiny batteries, and Yet-Ming Chiang, an expert on how to store energy in the form of a battery. "We're working on things we traditionally don't associate with nature." says Hammond. Many batteries are already pretty small. You can hold A, C and D batteries in your hand. The coin-like batteries that power watches are often smaller than a penny. However, every year, new electronic devices like personal music players or cell phones get smaller than the year before. As these devices shrink, ordinary batteries won't be small enough to fit inside. The ideal battery will store a lot of energy in a small package. Right now, Belcher's model battery, a metallic disk completely built by viruses, looks like a regular watch battery. But inside, its components are very small, so tiny you can only see them with a powerful microscope. How small are these battery parts? To get some idea of the size, pluck one hair from your head. Place your hair on a piece of white paper and try to see how wide your hair is pretty thin, right? Although the width of each person's hair is a bit different, you could probably fit about lots of these virus-built battery parts, side to side, across one hair. These micro-batteries may change the way we look at viruses.

单选题George Washington Carver was {{U}}esteemed{{/U}} for his contributions in the fields of botany and chemistry.

单选题下面的短文后列出了7个句子，请根据短文的内容对每个句子做出判断：如果该句提供的是正确信息，请选择A；如果该句提供的是错误信息，请选择B；如果该句的信息文中没有提及，请选择C。 {{B}}Green Roof Research{{/B}} The concept of green roofs is basically about growing plants on roofs, thus helping to replace the green footprint that had been destroyed due to the construction of the building. Green roofs are the most prevalent (流行) in Germany, which is widely regarded as the leader in green roof research. The green roofs that are used these days can be classified as 'extensive' and 'intensive' systems. Extensive green roofs use mosses, grasses and herbs, which are tolerant to droughts. These plants do not need much maintenance, can be grown in a layer of. substrata (土层) that can be as shallow as 1.5 inches, and generally are inaccessible to the public. In contrast, a wide range of species of plants are grown on intensive green roofs, such as shrubs (灌木) and even trees, which require deeper substrate layers, and are usually grown on flat roofs. They need intensive maintenance, and are' usually areas that resemble parks which are accessible to people. There are several benefits of adopting green roof technologies. Apart from the obvious psychological and aesthetic (美学的) benefits of garden-like environments surrounding you, some of the common economic and ecological benefits are.- a reduction in the consumption of energy; air and water purification; recovering green spaces; and the mitigation (缓解) of the heat island effect in urban areas. The green roof research that is currently ongoing is focused on evaluating the species of plants that are suitable to be grown on roofs, the methods of propagation (繁殖) as well as establishment, nutrient (养料) and water requirement, substrates, and the quantity and quality of water runoff. The evaluation criteria of plant species are: at what rate they can be established; their capacity to withstand invasive weeds; tolerance 'of cold, and heat; tolerance of drought conditions; capacity of persistence and survival. A number of experiments are being conducted on roof platform simulations at various research centers. These sites are generally outfitted with equipment, which are used to measure temperatures at different depths of the growing substrates, and the rate and volume of the runoff of stormwaters from each of the platforms. Green roof technology is representative of a completely new market for landscape contractors, and all roofs that currently exist and the future ones to be constructed are the potential market -- a market that is too huge to be overlooked.

单选题The winter was ______ cold, cat, sing great hardship to the poorer people in this area.A. exceptionallyB. explosivelyC. extensivelyD. expressively

单选题All houses within 100 metres of the seas are at risk of flooding.

单选题This kind of material was (seldom) used in building houses during the Middle Ages.

单选题It seems that only Mary is {{U}}eligible{{/U}} for the job. A. prepared B. trained C. guided D. qualified

单选题About one (quarter) of the workers in the country are employed in factories．

单选题The manager got angry just because his secretary, was ten minutes late.A. lost his moodB. lost his temperC. lost his mindD. lost his passion

单选题下面有3篇短文，每篇短文后有5道题，每题后面有4个选项。请仔细阅读短文并根据短文回答其后面的问题，从4个选项中选择1个最佳答案。{{B}}第一篇{{/B}} {{B}}Snowflakes{{/B}} You've probably heard that no two snowflakes are alike. Of course, nobody has ever confirmed that statement by examining every one of the estimated one septillion snowflakes that drift to Earth each year. Still, Kenneth Libbrecht, a professor at the California Institute of Technology, is confident that the statement is true. Snowflakes aren't flaky, says Libbrecht. At their basic level, they're crystalline. The lattice of every snowflake is six-sided in shape. The simplest snow crystals are six-sided flat plates and six-sided columns. Such crystals are common in places where the air is extremely cold and dry. Snow crystals acquire their special beauty when their simple six-sided symmetry blossoms. Under the right conditions, each of the six comers of a crystal sprouts what is called an arm. In a matter of minutes, the arms can become highly ornate and give the crystal a star like appearance. Several factors in the environment affect the shape and growth rate of a snow crystal. One factor is humidity. Crystals grow faster and in more intricate shape as humidity increases. A second factor is air temperature. A snowflake is born when several molecules of water vapor in a cloud land on a speck of dust and freeze to form a simple crystal. As the young crystal bops around in the cloud, it passes through air pockets of varying temperatures. If the crystal passes through a pocket of air that is, say, -15 degrees Celsius, it will grow quickly and sprout six arms, says Libbrecht. If the crystal is then tossed into a warmer pocket, one about -10℃, the arms' tips will stop growing quickly and form six-sided plates. If the crystal then drifts into an even warmer pocket of about -5℃, its top and bottom will grow more quickly than its sides and become more column like in shape. In the course of its life span, a snow-crystal might flutter through many warmer and colder pockets, acquiring a complicated and unique growth history. Such a history will give rise to a snowflake that is unlike any other. Each arm on the snowflake will look exactly like every other one, but the crystal itself will be one of a kind. Using his cooling tanks, Libbrecht has learned how to create snow crystals of different shapes -- plates, columns, needles, etc. Libbrecht has even refined his techniques so that he can make crystals that look highly similar to one another. Still, he lacks the control to manufacture identical twin snowflakes. A slight difference in humidity and temperature can upset the growth profile of a crystal.

单选题Can you make a sentence to bring out the meaning of the phrase?

单选题Centers of the Great European Cities The centers of the great cities of Europe are meeting places by tradition. People gather there to drink coffee and chat late into the night. A mixture of locals and tourists make for an exciting, metropolitan atmosphere. Squares, plazas(广场) and arcades(拱廊) form the heart of Europe"s cities. Venice in Italy has the Piazza San Marco-a beautiful square surrounded by shops, churches, restaurants and cafes. In Barcelona, Spain, La Bosqueria is a lively market with hundreds of stalls selling all kinds of goods. London"s Covent Garden is filled with fruit and vegetable stalls by day and musicians, acrobats(杂技演员) and artists by night. The government buildings at the center of many cities often are architecturally impressive. In London, they serve as a beautiful backdrop(背景) to the coffee tables that line the streets and the banks of the Thames. These vibrant(有活力的) hearts are the product of centuries of evolution, social historian Joel Garreau told US News and World Report recently. "The reason people think Venice is so great today is you don"t see all the mistakes," said Garreau, "those have all been removed." Most European cities were laid out before the invention of the car, so bars, restaurants and cafes were near to people"s homes. Today, the focus of many Europeans" life has moved away from the centers. They live in the suburbs and outskirts, driving to supermarkets to get their supplies. But on a continent where people treasure convention, there are still those who hold onto traditional ways, living and shopping locally. These people, together with tourists, provide the city centers with their reason for existence. Coffee culture plays a part in keeping these city centers flourishing. This is particularly true of Paris whose citizens are famous enthusiastic conversationalists. This skill is developed over many hours spent chatting over espressos(浓咖啡) and cigarettes. Religion also plays a role in developing sociable atmosphere. People in Roman Catholic countries used to visit the Church on an almost daily basis. Entire communities would gather in the same building and then move out to the markets, cafes and bars in the surrounding streets. An enormous example of this relationship between church and society is the Duomo. The huge marble cathedral in Florence, Italy is surrounded by bakeries and coffee shops, and caters not only to the tourist crowds, but also the local community.

单选题______ by the police, the robbers had no choice but to surrender.A. To be surroundedB. SurroundedC. SurroundingsD. To surround

单选题Don"t be afraid . I am not going to hurt you.

单选题Easy Listening Students should be jealous. Not only do babies get to doze their days away, but they've also mastered the fine art of learning in their sleep. By the time babies are one year old, they can recognize a lot of sounds and even simple words. Marie Cheour at the University of Turku in Finland suspected that they might progress this fast because they learn language while they sleep as well as when they are awake. To test the theory, Cheour and their colleagues studied 45 newborn babies in the first days of their lives. They exposed all the infants to an hour of Finnish vowel sounds one that sounds like "oo"; another like "ee" and the third boundary vowel peculiar to Finnish and similar languages that sounds like something in between. EEG (脑电图) recording of the infants brains before and after the session showed that the newborns could not distinguish the sounds. Fifteen of the babies then went back with their mothers, where the rest were split into two sleep-study groups. One group was exposed throughout their night-time sleeping hours to the same three vowels, while the others listened to the other, easier-to-distinguish vowel sounds. When tested in the morning, and again in the evening, the babies who'd heard the tricky boundary vowels all night showed brainwave activity indicating that they could now recognize this sound. They could identify the sound even when its pitch was changed, while none of the other babies could pick up the boundary vowel at all. Cheour doesn't know how babies accomplish this nighttime learning, but she suspects that the special ability might indicate that unlike adults, babies don't "turn oft" their cerebral cortex (大脑皮层) while they sleep: The skill probably fades in the course of the first years of life, she adds so forget the idea that you can pick up the tricky French vowels as an adult just by slipping a language tape under your pillow. But while it may not help grown-ups, Cheour is hoping to use the sleeping hours to give remedial help to babies who are genetically at risk of language disorders.

单选题The chemical is {{U}}deadly{{/U}} to rats but safe to cattle.