单选题There is a controversy even among doctors as to whether this disease is contagious or not.

单选题Born ten days earlier, the boy ______ his late father. A. could have seen B. must have seen C. may have seen D. should have been

单选题Violent criminals with something to hide have more reason than ever to be paranoid about a tap on the shoulder which could send them to jail. Queensland police are working through a backlog of unsolved murders with some dramatic success. Greater cooperation between the public and various law enforcement agencies is playing a role, but new genetic-testing techniques are the real key to providing the vital evidence to mount a prosecution. Evidence left behind at the scene of any murder is guaranteed to outlive the person who left it. A blood, saliva or tissue sample the size of a pin, kept dry and out of sunlight, will last several thousand years. From it, scientific analysis now can tell accurately the sex of the person who left it. When matched against a sample from a crime suspect, it can indicate with million-to-one certainty whether the samples come from the same source. Only twins share identical DNA. So precise is the technology if the biological parents of a suspect agree to provide a sample, forensic scientists can work out the rest for themselves without cooperation from the suspect. Queensland forensic scientists have been using the DNA testing technology since 1992, and last year they were recognized internationally for their competence in positive individual identification. That is part of the reason 20 of Queensland's most puzzling unsolved murders dating to 1952 are being actively investigated. There also have been several recent arrests for unsolved murders. Forensic evidence was instrumental in charges being laid over the bashing death of waitress Tasha Douty on Brampton Island in 1983. Douty's blood-splattered, naked body was found on a nude sunbathing beach at Dinghy Bay on the island. Footprints in the sand indicated that the killer had grappled with the 41-year-old mother who had fled up the beach before being caught and beaten to death. According to Leo Freney, the supervising forensic scientist at the John Tonge Centre at Brisbane's Griffith University, DNA testing has become an invaluable tool for police. Its use is in identifying and rejecting suspects. In fact, he says, it eliminates more people that it convicts. "It is easily as good as fingerprints for the purpose of identification," he says. "In the case of violent crime it is better than fingerprints. You can't innocently explain things like blood and semen at a crime scene where you may be able to innocently explain fingerprints. " In Queensland, a person who has been arrested on suspicion of an offence can be taken before a magistrate and ordered to provide a sample of body fluid by force if necessary.

单选题The Aerospace Bicycle That Fell to Earth A radical new bicycle had its first public showing at the National British Cycling Championships in Shrewsbury last weekend. Based on the gold medal-winning design from the Barcelona Olympics, it is the first commercial mountain bike made of a single piece of carbon fibre. Bicycles for amateurs have up to now been made of steel, aluminum or magnesium tubes welded together into the conventional "A-frame"shape. But last year, the British competitor Chris Boardman set world records while winning titles in the Olympic cycling pursuit events on a custom built, carbon-fibre bicycle with lower weight and wind resistance than standard models. Because carbon fibre is both light and extremely strong, it does not need the A-frame shape, saving further weight. Carbon fibre can also be moulded in a single piece, avoiding the weakness of welds. The new bike, which will cost between $ 2000 and $ 3000 when it reaches the shops next month, has the same advantages as the Olympic model. It weighs about 11 kilograms,a saving of 1.5 kilograms on metal frames. With no crossbar, it has a lower center of gravity, making it easier to use in race conditions. "When you're doing some aggressive riding,you throw the bike about from side to side," explains Eddie Eccleston, director of British Eagle, a British bicycle manufacturer based in Powys, Wales, which is marketing the bikes. "The low centre of gravity gives you better control. " The frames are being made in the U. S. for British Eagle by SP systems in Camarillo,California, which has clients in the aerospace industry, "This is aerospace technology brought into cycling by enthusiasts", says Eccleston. When professionals tested racing versions of the bike before the Tour de France, they were quicker than metal versions by up to 3 seconds per kilometer. The new design has no struts between the saddle and the back wheel; instead, the frame's flexibility can be "tuned" to individual tastes by changing the mixture of Kevlar fibre and carbon fibre in the back wheel strut, allowing up to 5 centimeters of movement. The carbon-fibre design has a lower centre of gravity and smoother back-wheel suspension than conventional bikes.

单选题It was exciting to see such a movie for first time, but we soon became ______ when our TV was flooded with programs of like-kind.

单选题It was at the exhibition that we______this kind of minicar made of plastics.

单选题Data security used to be all about spending big bucks on firewalls to defend data at the network perimeter and on antivirus software to protect individual computers. Internet-based computing, or cloud computing, has changed all that, at the same time expanding exponentially the chances for data thieves and hackers. The cloud creates other opportunities too. a handful of security vendors now deliver security as a service--a one-two punch of hardware and software that monitors and manages an enterprise's data security and bills customers only for the computing power they use. "For years, security was about big companies pushing technology to their customers," says Qualys CEO and founder Philippe Courtot. "Now it's about the customers pulling precisely what they need and providing them with those resources on demand. " Qualys, a privately held company in Redwood Shores, Calif. , was among the first to embrace the service-oriented model, in 1999. Today four different modules of QualysGuard, its flagship offering, are used by more than 3500 organizations in 85 countries. The company performs more than 200 million security audits per year. Courtot knows something about opportunity. The French entrepreneur arrived in Silicon Valley in 1987 and has built a number of companies into big-time players, including Signio, an electronic-payment start-up that was eventually sold to VeriSign in a combined deal for more than $1 billion. As CEO, he rebuilt Verity and transformed cc:Mail, a once unknown firm of 12 people, into a dominant e-mail platform before Lotus acquired it in 1991. "Throughout my career, I've been able to recognize that for a technology to succeed, it must have a purpose," he says. "Technology itself has no value. It's what you do with it that counts. " Under the old paradigm, according to Courtot, enterprises overspent for stand-alone security devices that became unruly and difficult to operate over the long term He says Qualys attacks the flaws in this strategy by streamlining security and tackling most of the service delivery through the cloud. "We control the infrastructure, software updates, quality assurance and just about everything in between," he says. The firm unveiled QualysGuard in 2000. After an infusion of $ 25 million from the venture firm Trident Capital and another $ 25 million from Gourtot, Qualys tweaked the service to focus mostly on vulnerability management. Much of the company's current revenue-sales, topped $ 50 million last year--is being driving by a set of standards established by the Payment Card Industry Security Standards Council (PCISSC). "The PCI standard has been a major driver of business for all of them, especially Qualys," says Avivah Litan, a vice president and analyst at market-research firm Gartner. "When everyone has to comply, there's a lot of work to go around. /

单选题No culture exists in{{U}} {{/U}} . It all comes from someplace. Ancient customs were modern one time.

单选题{{B}}Passage 2{{/B}} In the old days, sending a thank-you note to a relative was easy. You wrote it, {{U}}(1) {{/U}} , a stamp on the envelope and dropped it {{U}}(2) {{/U}} a mailbox. {{U}}(3) {{/U}} it went in a red-white-and-blue U.S. Mail truck, and {{U}}(4) {{/U}} of days later the friendly neighborhood mailman walked it, {{U}}(5) {{/U}}. weather, right to the recipient's door. {{U}} (6) {{/U}} you’re as likely to send a fax, e-mail, or instant message. {{U}}(7) {{/U}} you cling to traditional pen and paper, it's no longer clear (8) it will travel. Airborne Express? Overnight? Two-Day Priority? {{U}} (9) {{/U}} it moves into the 1st century, the American mail system {{U}}(13) {{/U}} to survive. In the past few years, the U.S. Postal Service(USPS) has {{U}}(11) {{/U}} many new services, {{U}}(12) {{/U}} stamps over the Internet, electronic bill payment, and a service that prints and mails electronic documents Yet revenues depleted by alternative communications (e-mail, electronic banking), {{U}}(13) {{/U}} with rising fuel and operating costs, led to a $150 million loss in 2000. Meanwhile, private carriers are competing {{U}}(14) {{/U}} business, forcing the Postal Service to contract with the likes of DHL and Emery Worldwide just to maintain its global reach. {{U}}(15) {{/U}} still delivering 20 percent of the world's mail, the men and women in the blue uniforms of the Postal Service just can't seem to {{U}}(16) {{/U}}. The problem is that the U.S. hasn't {{U}}(17) {{/U}} grips with the fact that in a fast-changing world, mail delivery is better run as a competitive business than as a government monopoly. {{U}}(18) {{/U}} many countries have privatized their postal systems, the USPS has attempted to maintain business in both the public and private worlds. It is a semiprivate corporation with a lumbering government bureaucracy. It is {{U}}(19) {{/U}} by a board of governors {{U}}(20) {{/U}} a blend of local politicians, small-town business leaders and federal bureaucrats.

单选题We learn from Paragraph 2 that ______.

单选题Americans usually consider themselves a friendly people. Their friendships, however, tend to be shorter and more casual than friendships among people from other cultures. It is not uncommon for Americans to have only one close friend during their lifetime, and consider other "friends" to be just social acquaintances. This attitude probably has something to do with American mobility and the fact that Americans do not like to be dependent on other people. They tend to "compartmentalize (划分) friendships, having "friends at work", "friends on the softball team", "family friends", etc. Because the United States is a highly active society, full of movement and change, people always seem to be on the go. In this highly changed atmosphere, Americans can sometimes seem brusque (无礼的) or impatient. They want to get to know you as quickly as possible and then move on to something else. Sometimes, early on, they will ask you questions that you may feel very personal. No insult is intended; the questions usually grow out of their genuine interest or curiosity, and their impatience to get to the heart of the matter. And the same goes for you. If you do not understand certain American behavior or you want to know more about them, do not hesitate to ask them questions about themselves. Americans are usually eager to explain all about their country or anything "American" in which you may be interested. So much so in fact that you may become tired of listening. It doesn"t matter because Americans tend to be uncomfortable with silence during a conversation. They would rather talk about the weather or the latest sports scores, for example, than deal with silence. On the other hand, don"t expect Americans to be knowledgeable about international geography or world affairs, unless those subjects directly involve the United States. Because the United States is not surrounded by many other nations, some Americans tend to ignore the rest of the world.

单选题Peter is used to a simple way of living. He doesn't want to ______ so much money on food or clothing.

单选题{{B}}Passage Three{{/B}} The wandering ship was a dramatic symbol for a problem plaguing our age. In 1987, the ship, loaded with thousands of tons of New York garbage, spent weeks wandering from one port to another in search of a dump before finally returning home, mission unaccomplished. New York, like other communities throughout the world is running out of space to put its trash. As throwaway societies, the US and other industrialized countries expect their garbage to be picked up by trucks that magically transported the refuse to some out-of-sight incinerator(焚化炉) or dump. But in the developing counties of Asia, Africa and Latin America, thousands of tons of trash collected daily are thrown into open dumps, where it feeds huge populations of rats that swarm through poor neighborhoods. "The world is literally swimming in garbage," says a scientist, "Communities worldwide are being forced to confront the problem." Green Peace spokesman Bryan Bence adds, "The crisis in garbage stems in part from the fact that we've ignored long-term disposal problem in favor of cheap quick fixes." The garbage glut (过选剩) has inspired many communities in the U.S., Japan and Western Europe to start recycling programs. Once considered a curious counter culture activity recycling has moved firmly into the mainstream. Recycling involves separating usable products from trash, processing them so they can be substituted for more expensive raw materials and returning them to the marketplace as parts of new products. Many countries now have mandatory recycling programs, and others plan to follow the trend soon. Most notably, Japan has stood out as a model and leader of the waste management trend, recycling an estimated 65 percent of its waste. "That's what we should do, to the garbage crisis", says David Antonioli, a staff member with the New York Public Interest Research Corp. "The earth is not a dump!"

单选题The policeman saw the thief ______ he appeared on the street corner. A) not until B) as long as C) the moment D) only if

单选题When global warming finally came, it stuck with a vengeance. In some regions, temperatures rose several degrees in less than a century. Sea levels shot up nearly 400 feet, flooding coastal settlements and forcing people to migrate inland. Deserts spread throughout the world as vegetation shifted drastically in North America, Europe and Asia. After driving many of the animals around them to near extinction, people were forced to abandon their old way of life for a radically new survival strategy that resulted in widespread starvation and disease. The adaptation was farming: the global-warming crisis that gave rise to it happened more than 10,000 years ago. As environmentalists convene in Rio de Janeiro this week to ponder the global climate of the future, earth scientists are in the midst of a revolution in understanding how climate has changed in the past—and how those changes have transformed human existence. Researchers have begun to piece together an illuminating picture of the powerful geological and astronomical forces that have combined to change the planet"s environment from hot to cold, wet to dry and back again over a time period stretching back hundreds of millions of years. Most important, scientists are beginning to realize that the climatic changes have had a major impact on the evolution of the human species. New research now suggests that climate shifts have played a key role in nearly every significant turning point in human evolution: from the dawn of primates some 65 million years ago to human ancestors rising up to walk on two legs, from the huge expansion of the human brain to the rise of agriculture. Indeed, the human history has not been merely-touched by global climate change, some scientists argue, it has in some instances been driven by it. The new research has profound implications for the environmental summit in Rio. Among other things, the findings demonstrate that dramatic climate change is nothing new for planet Earth. The benign global environment that has existed over the past 10,000 years—during which agriculture, writing, cities and most other features of civilization appeared—is a mere bright spot in a much larger pattern of widely varying climate over the ages. In fact, the pattern of climate change in the past reveals that Earth"s climate will almost certainly go through dramatic changes in the future—even without the influence of human activity.

单选题— How do you ______ we go to Beijing for our Holidays? — I think we'd better fly there. It's much comfortable.A. insistB. wantC. supposeD. suggest

单选题Democrats on the Senate Judiciary Committee vented their fury over high gasoline prices at executives of the nation"s five largest oil companies on Wednesday, grilling the oilmen over their multimillion-dollar pay packages and warning them that Congress was intent on taking action that could include a new tax on so-called windfall profits. Such showdowns between lawmakers and oil titans have become a familiar routine on Capitol Hill. But with gas prices nearing $ 4 a gallon, and lawmakers headed home for a weeklong Memorial Day recess where they expect to get an earful from angry constituents, there is added urgency for Congress to appear active. But while momentum is building for several measures, including a bill that would allow the Organization of the Petroleum Exporting Countries to be sued in American courts under antitrust laws, there is little sign that any of the proposals would do much, if anything, to lower prices quickly. And the oil executives warned that government intervention might only make things worse. Instead, they called on Congress to allow more drilling and exploration for domestic oil. The increasing urgency to seem aggressive about gasoline prices was apparent on Tuesday when the House voted by an overwhelming 324 to 84 to approve the bill, commonly referred to as NOPEC, which classifies OPEC as a monopoly in violation of the Sherman Antitrust Act. Senate Democrats have included that measure as part of a package of legislation intended to address the high price of gasoline, along with the tax on windfall profits and a measure to tamp down speculation in the oil futures market that many lawmakers think is contributing to the run-up in prices. At the Judiciary Committee hearing, Democratic senators struggled to have the executives explain how oil prices had risen so high. The senators expressed doubt that basic laws of supply and demand were at work and suggested instead a more sinister combination of monopolistic behavior by oil-producing countries, speculation in the futures markets and sheer corporate greed. On Monday, President Bush signed a bill temporarily suspending the purchase of crude oil for the nation"s Strategic Petroleum Reserve. Mr. Bush had initially opposed such action but relented after the House and Senate approved the bill by wide margins. Senator Richard J. Durbin, Democrat of Illinois and a strong supporter of Senator Baraek Obama"s presidential bid, made a particularly pointed attack, in which he seemed to warn the oil executives that they would soon no longer have such a good friend in the White House. He also suggested that Mr. Bush should be doing more to press the oil companies to help lower prices at the pump, while acknowledging that it would be difficult to pass a windfall profits tax while Mr. Bush was still in office.

单选题In some remote places, there are still very poor people who can't afford to live in ______ conditions. A. positive B. gracious C. honorable D. decent

单选题Since time immemorial, countless scholars have asked the question: What is beauty? As philosophers engage in weighty discourses, designers update the latest fashions, and artists create their masterpieces, what is considered beautiful changes at an alarming pace. Fifty years ago, the full-figured Marilyn Monroe embodied the American aesthetic value; today, a legion of Hollywood actresses vastly different in appearance from Marilyn"s have taken her place. However, aesthetic values not only differ from generation to generation, but do so along cultural lines as well. The conventions that govern painting and music vary greatly from East to West. Often, what is considered disgusting to one civilization is the pinnacle of aesthetic appeal in another. Thus, when left to the sphere of human design, the search for an absolute definition of beauty remains an elusive one at best. As fundamental physicists, my colleagues and I like to believe that we are involved in a search for a beauty that does not remain uninfluenced by definition; The beauty that we search for is not that which is laid down through the work of people and subject to short-term tastes, but rather that which has been established by Nature. Those not involved with physics tend to think of it as a precise and predictive science—certainly not a field of study fit for the contemplation of the beautiful. Yet, one of physics"s greatest gifts is that it allows its students to look past extrinsic appearances into a more overwhelming beauty. As a human being, I am captivated by the visual appeal of a wave crashing on the beach. As a physicist, however, I possess the ability to be captivated by the much deeper beauty of the physical laws that govern such a phenomenon. Where the nonphysicist sees a lovely but inexplicable event, the well-schooled physicist is able to perceive a brilliant design. In truth, since the day that Albert Einstein first proposed the notion that there might be one overarching physical theory that governs the universe, aesthetics has become a driving force in modern physics. What Einstein and we, as his intellectual descendants, have discovered is this;Nature, at its most fundamental level, is beautifully constructed. The remarkable simplicity of the laws that govern the universe is, at times, nothing short of breathtaking. And at every step, as new discoveries and technologies allow us to examine the physical world on deeper and deeper levels, we find that the beauty itself becomes more profound. As Einstein himself said, it would seem more likely that we should find ourselves living in a " chaotic world, in no way graspable through thinking. " Yet here we are, closer than ever to a full understanding of the universe"s beautiful clockwork.