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设S为学生关系，Sc为学生选课关系，Sno为学生号，Cno为课程号，执行下面SQL语句查询结果是 (30) 。Select S. * From S，SC Where S. Sno=Sc. Sno and Sc. Cno=’c2’
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TEXT D Two conflicts convinced Western countries that they dared not reduce their forces too drastically, The first was the Iraqi invasion of Kuwait in August 1990. This came at the height of the happiness at the end of the Cold War and the new era of peace that was expected to follow. By January 1991 it was apparent that attempts to persuade Iraqi leader Saddam Hussein to withdraw through a combination of military threats, economic pressure, and diplomatic inducements had failed. American, British, and French forces found themselves using military equipment and concepts designed to deal with the Warsaw Pact in central Europe to defeat a moderate-sized Third World country. This brought home the lesson that in a world in which total war had become too horrific to contemplate even a limited war was no small matter and would demand considerable commitment. Even so, the Gulf War was a relatively straightforward confrontation. It was against a known enemy over a clear-cut matter of principle and fought by means that played to the West’s comparative advantages, for example in air power. To defense planners, this was much to be preferred to the considerably more complicated types of conflict where opponents merged easily into their surroundings, and adopted guerrilla warfare rather than open battle. Prudent defense planners never want to get involved in messy civil wars, while the military dislikes having to get between warring groups. It is usually easier to get in than out of these conflicts. Yet even as troops were returning from the Gulf in the summer of 1991, Yugoslavia was starting to fall apart. By 1992, British and French forces were being deplored in Bosnia, along with contingents from other countries, to try to deliver humanitarian aid and soften the blows of a bitter ethnic conflict. Eventually, in 1995, now joined by the Americans, they began to take a much tougher line and this created the conditions for a political settlement, although not an early withdrawal of outside forces. They were still needed to keep the peace. The experience of these conflicts illustrates some of the difficulties now faced by defense planners. They must prepare for a wide range of operations, from set-piece battles to vicious inter-communal skirmishes. Even though they may hope that total wars are things of the past for the major industrialized countries, limited wars might still require the sort of capabilities once assumed to be relevant only to total wars. Limited wars also come in all shapes and sizes. In 1982 the Falklands War was won through achieving naval superiority followed by an amphibious landing, while in 1991 Kuwait was liberated through air supremacy followed by a heavy armored advance. The first stage of the Gulf crisis involved a naval blockade -- the last stage involved light forces protecting Kurds. Bosnia involved a hybrid force of infantry geared to a low-intensity conflict supported by air power conducting a high-intensity campaign. Future conflicts might involve direct attacks on environmental targets or attempts to exploit the West’s growing dependence on information technology. Terrorism and international criminal organizations are now often presented as the most serious threats to Western societies. The main idea of the article is about ______.
In this section there are several reading passages followed by a total of twenty multiple-choice questions. Rend the passages carefully and then mark your answers on your coloured answer sheet.TEXT A Linguists have found that sign languages and spoken languages share many features. Like spoken languages, which use units of sounds to produce words, sign languages use units of form. These units are composed of four basic hand forms: hand shape, such as an open hand or closed fist; hand location, such as on the middle of the forehead or in front of the chest; hand movement, such as upward or downward; and hand orientation, such as the palm facing up or out. In spoken languages units of sound combine to make meaning. Separately, b, e, and t have no meaning. However, together they form the word bet. Sign languages contain units of form that by themselves hold no meaning, but when combined create a word. Spoken languages and sign languages differ in the way these units combine to make words, however. In spoken languages units of sound and meaning are combined sequentially. In sign languages, units of form and meaning are typically combined simultaneously. In American Sign Language (ASL) signs follow a certain order, just as words do in spoken English. However, in ASL one sign can express meaning that would necessitate the use of several words in speech. For example, the words in the statement "I stared at it for a long time" each contain a unit of meaning. In ASL, this same sentence would be expressed as a single sign. The signer forms "look at" by making a V under the eyes with the first and middle fingers of the right hand. The hand moves out toward the object being looked at, repeatedly tracing an oval to indicate "over a long time". To express the adverb "intently" the signer squints the eyes and purses the lips. (To purse the lips is like saying mmmm: pull back and tighten the lips with the lips closed.) Although the English words used to describe the ASL signs are written out in order, in sign language a person forms the signs "look at", "long time", and "intently" at the same time. ASL has a rich system for modifying the meaning of signs. Verbs such as "look at" can be changed to indicate that the activity takes place without interruption, repeatedly, or over a long time. The adjective "sick", for example, is formed by placing the right middle finger on the forehead and the left middle finger on the stomach. By forming the sign "sick" and repeatedly moving the left hand in a circle, the signer can indicate that someone is characteristically or always sick. Facial grammar, such as raised eyebrows, also can modify meaning. For example, a signer can make the statement "lie is smart" by forming the ASL sign for "smart" --placing the middle finger at the forehead -- and then quickly pointing it outward as if toward another person to indicate "he". To pose the question "Is he smart" the signer accompanies this sign with raised eyebrows and a slightly tilted head. People who sign sometimes use finger spelling to represent letters of the alphabet. In some sign languages, including ASL, finger spelling serves as a way to borrow words from spoken language. A deaf person might, for example, choose to fingerspell "d-o-g" for "dog" instead of using a sign. Several types of finger spelling systems exist. Linguists still have much to learn about the world’s sign languages. What has become clear is that hundreds, if not thousands, of sign languages exist around the world. What is the main idea of the passage
TEXT C American Indian Movement (AIM) is an organization devoted to promoting cultural awareness and political self-determination for Native Americans. AIM seeks recognition of treaty rights in accordance with agreements between Native American tribes and the United States government. The organization also supports Native American education and cultural programs. AIM is best known for its confrontational political demonstrations during the late 192s and 1970s. AIM was founded in 1968 in Minneapolis, Minnesota, in response to complaints by Native American residents about police brutality. Members of the organization began to monitor police behavior. As the group gained strength, they also started to lobby for improved city services for the many Native Americans living in run-down tenant apartments, and they developed survival schools where Native American youths could be taught about their culture. Over the next four years, AIM expanded throughout the country, forming 40 chapters in cities and on reservations. AIM leaders, such as Dennis Banks and Russell Means, became well-known spokesmen for Native American rights. AIM participated in a number of high-profile demonstrations from the late 192s through the late 1970s. From November 1969 to June 1971, AIM members participated in a 19-month occupation of Alcatraz Island, site of an abandoned federal prison in San Francisco Bay. The protest was intended to draw attention to the poor conditions of Native American reservations throughout the United States. The protesters proposed establishing a center for Native American studies on the island. Another group of Native Americans, allied with AIM, occupied a surplus military facility in Davis, California, beginning in October 194. These actions resulted in the establishment of Native American-controlled D-Q University in Davis in 1971. D-Q University is named for Deganawidah, an Iroquois prophet, and Quetzelcoatl, the Aztec god of peace and civilization. AIM staged many demonstrations to protest the U.S. government’s treatment of Native Americans and the loss of their ancestral lands. In 1970 organization members participated in an occupation of a portion of Mount Rushmore National Monument in the Black Hills of South Dakota. Two years later, AIM members staged a Thanksgiving Day protest at Plymouth, Massachusetts, where the Pilgrims had landed in 1620, and briefly occupied a replica of the Pilgrim ship, the Mayflower. AIM played a critical role in organizing the 1972 "Trail of Broken Treaties". Native American protesters converged on Washington, D.C., just before the presidential election in November. Marchers met with government officials at the Bureau of Indian Affairs (BIA) to present a 20-point program of demands. With police massed outside, marchers look over the BIA building and renamed it the "Native American Embassy". The occupation ended after authorities agreed to appoint a committee to study the demands and not to arrest the protesters. The next major AIM action was the 1973 occupation of the town of Wounded Knee, the site of an infamous massacre of Native Americans by U.S. troops in 1890. Invited by tribal elders to protest a corrupt tribal government, AIM members and local allies took over the tiny hamlet. They were soon surrounded by agents from the Federal Bureau of Investigation (FBI), U.S. marshals, and the BIA police. The ensuing siege lasted for 70 days and ended in a standoff. A committee was appointed to examine the grievances that had led to the occupation, but no official action was ever taken. AIM began to splinter apart. The organization’s national office closed in 1975, and all national officer positions were dissolved in 1979. Although AIM staged "The Longest Walk", a 1978 march from California to Washington, D.C., to protest bills introduced to the U.S. Congress that would reduce or abolish Native American treaty rights, the group foundered without national leadership. The 1990s have seen a modest revival of the organization. In 1992 local AIM chapters protested the celebrations marking the 500-year anniversary of Columbus’s first voyage to America. At a 1993 conference in New Mexico, 16 local AIM groups organized themselves as the Confederation of Autonomous AIM Chapters. According to the passage, which of the following statement is NOT true
TEXT E Patents, said Thomas Jefferson, should draw "a line between the things which are worth to the public the embarrassment of an exclusive patent, and those which are not". As the value that society places on intellectual property has increased, that line has become murkier--and the cause of some embarrassment, too. Around the world, patent offices are being inundated with applications. In many cases, this represents the extraordinary inventiveness that is occurring in new fields such as the internet, genomics and nanotechnology. But another, less-acceptable reason for the flood is that patent offices have been too lax in granting patents, encouraging many firms to rush to patent as many, often dubious, ideas as possible in an effort to erect legal obstacles to competitors. The result has been a series of messy and expensive court baffles, and growing doubts about the effectiveness of patent systems as a spur to innovation, just as their importance should be getting bigger. In 1998 America introduced so-called "business-method" patents, granting for the first time patent monopolies simply for new ways of doing business, many of which were not so new. This was a mistake. It not only ushered in a wave of new applications, but it is probably inhibiting, rather than encouraging, commercial innovation, which had never received, or needed, legal protection in the past. Europe has not, so far, made the same blunder, but the European Parliament is considering the easing of roles for innovations incorporated in software. This might have a similarly deleterious effect as business-method patents, because many of these have been simply the application of computers to long-established practices. In Japan, firms are winning large numbers of patents with extremely narrow claims, mostly to obfuscate what is new and so to ward off rivals. As more innovation happens in China and India, these problems are likely to spread there as well. There is an urgent need for patent offices to return to first principles. A patent is a government-granted temporary monopoly (patents in most countries are given about 20 years’ protection) intended to reward innovators in exchange for a disclosure by the patent holder of how his invention works, thereby encouraging others to further innovation. The qualifying tests for patents are straightforward--that an idea be useful, novel and not obvious. Unfortunately most patent offices, swamped by applications that can run to thousands of pages and confronted by companies wielding teams of lawyers, are no longer applying these tests strictly or reliably. For example, in America, many experts believe that dubious patents abound, such as the notorious one for a "sealed crustless sandwich". Of the few patents that are re-examined by the Patent and Trademark Office itself, often after complaints from others, most are invalidated or their claims clipped down. The number of duplicate claims among patents is far too high. What happens in America matters globally, since it is the world’s leading patent office, approving about 170,000 patents each year, half of which are granted to foreign applicants. Europe’s patent system is also in a mess in another regard: the quilt of national patent offices and languages means that the cost of obtaining a patent for the entire European Union is too high, a burden in particular on smaller firms and individual inventors. The European Patent Office may award a patent, but the patent holder must then file certified translations at national patent offices to receive protection. Negotiations to simplify this have gone on for over a decade without success. As a start, patent applications should be made public. In most countries they are, but in America this is the case only under certain circumstances, and after 18 months. More openness would encourage rivals to offer the overworked patent office evidence with which to judge whether an application is truly novel and non-obvious. Patent offices also need to collect and publish data about what happens once patents are granted--the rate at which they are challenged and how many are struck down. This would help to measure the quality of the patent system itself, and offer some way of evaluating whether it is working to promote innovation, or to impede it. But most of all, patent offices need to find ways of applying standards more strictly. This would make patents more difficult to obtain. But that is only right. Patents are, after all, government-enforced monopolies and so, as Jefferson had it, there should be some "embarrassment" (and hesitation) in granting them. What’s wrong with Europe’s patent system
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