单选题Once you get to know your mistakes, you should ______ them as soon as possible.

单选题4 Some African Americans have had a profound impact on American society, changing many people's views on race, history and politics. The following is a sampling of African Americans who have shaped society and the world with their spirit and their ideals. Muhammad Ali Cassius Marcellus Clay grew up a devout Baptist in Louisville, Ken- tucky, learning to fight at age 12 after a police officer suggested he learn to defend himself. Six years later, he was an Olympic boxing champion, going on to win three world heavyweight titles. He became known as much for his swagger (趾高气昂) outside the ring as his movement in it, converting to Islam in 1965, changing his name to Muhammad All and refusing to join the U.S. Army on religious grounds. Ali remained popular after his athletic career ended and he developed Parkinson's disease, even lighting the Olympic torch at the 1996 Atlanta Olympics and conveying the peaceful virtues of Islam following the September 11 terrorist attacks. W. E. B. Du Bois Born William Edward Burghardt Du Bois in 1868, this Massachusetts native was one of the most prominent, prolific intellectuals of his time. An academic, activist and historian, Du Bois co-founded the National Association for the Advancement of Colored People (NAACP), edited The Crisis magazine and wrote 17 books, four journals and many other scholarly articles. In perhaps his most famous work, The Souls of Black Folk, published in 1903, he predicted "the problem of 20th century [would be] the problem of the color-line. " Martin Luther King Jr. The Rev. Martin Luther King Jr. is considered one of the most powerful and popular leaders of the American civil rights movement. He spearheaded (带头，作先锋) a massive, nonviolent initiative of marches, sitins, boycotts and demonstrations that profoundly affected Americans' attitudes toward race relations. He was awarded the Nobel Peace Prize in 1964. Malcolm X Black leader Malcolm X spoke out about the concepts of race pride and black nationalism in the early 1960s. He denounced the exploitation of black people by whites and developed a large and dedicated following, which continued even after his death in 1965. Interest in the leader surged again after Spike Lee's 1992 movie Malcolm X was released. Jaekie Robinson In 1947, Jackie Robinson broke the color barrier by joining the Brooklyn Dodgers, becoming the first black baseball player in the U. S. major leagues. After retirement from baseball in 1957, he remained active in civil rights and youth activities. In 1962, he became the first African-American to be inducted into the Baseball Hall of Fame.

单选题Many societies today interpret the natural world and form beliefs based on science and logic. Societies in which many people do not practice any religion, such as the United States, may be known as______societies.

单选题Not until the advent of histochemistry could the anatomist see through the microscope which cells carry specific enzymes or gauge how active these enzymes are in different cells under various conditions.

单选题As a writer Walkter was very ______.

单选题A censor's duty is to ensure that no content is ______ in publications or films.

单选题My colleagues and I were greatly puzzled by our repeated failures in the experiment.

单选题From Christianity and the barbarian kingdoms of the west emerged the medieval version of politics______.in turn evolved the politics of our modern world. A. of which B. from which C. on which D. by which

单选题in science the meaning of the word "explain" suffers with civilization"s every step in search of reality. Science cannot really explain electricity, magnetism, and gravitation; their effects can be measured and predicted, but of their nature no more is known to the modem scientist than to Thales who first speculated on the electrification of amber. Most contemporary physicists reject the notion that man can ever discover what these mysterious forces "really" are. "Electricity," Bertrand Russell says, "is not a thing, like St. Paul"s Cathedral; it is a way in which things behave. When we have told how things behave when they are electrified, and under what circumstances they are electrified, we have told all there is to tell." Until recently scientists would have disapproved of such an idea. Aristotle, for example, whose natural science dominated Western thought for two thousand years, believed that man could arrive at an understanding of reality by reasoning from self-evident principles. He felt, for example, that it is a self-evident principle that everything in the universe has its proper place, hence one can deduce that objects fall to the ground because that"s where they belong, and smoke goes up because that"s where it belongs. The goal of Aristotelian science was to explain why things happen. Modem science was born when Galileo began trying to explain how things happen and thus originated the method of controlled experiment which now forms the basis of scientific investigation.

单选题The synthetic fibers produced in that large factory Uaccount for /Uone third of all the fibers turned out in the area.

单选题The______ include paintings and photos showing the life of the people.

单选题The law prohibits occupancy by more than 250 persons in this area. A. forbids B. allows C. promises D. suggests

单选题Although it was his first experience as chairman, he ______ over the meeting with great skill. [A] presided [B] administered [C] mastered [D] executed

单选题{{B}}Passage 4{{/B}} Everything in today's world is going faster and faster, and television commercials are no exception. At the start of the television age the standard commercial lasted 60 seconds, but most of today's commercials are only half that length and many are even shorter. The 15-second commercial, introduced a few years ago as a way to cut skyrocketing advertising costs, may soon be the most common in the United States. (Our television-watching counterparts in Japan and Europe are already being treated to 7-second mini-commercials ! ) What stands behind the message that blips onto and off our television screens before we have time to get to the kitchen and hack? Months of planning; hundreds of interviews with potential users of the product; hours of writing; dozens of actors, directors, and technicians; days of filming; and hundreds of thousands of dollm's in payments to the television networks that will run the ad. Take for example a recent commercial for a certain brand of cough drops. The manufacturer of the cough drops spent four months trying to think of a way to boost sales. After several surveys of cough drop users, the company decided to market a strawberry-flavored lozenge. Further surveys identified tile typical users of the strawberry-flavored cough drop as persons between the ages of 15 and 30. This infforination was important in planning the content and style of the commercial (fast-paced and upbeat, with colorful graphics and lively music) and in determining when to air it (during situation comedies, prime-time dramas, and music specials). The creative team at the advertising agency that handled the cough drop company's account then took over. After hours of discussion and writing, they came up with six scripts, from which the client chose two. One involved a young woman pulling a strawberry out of a box of cough drops. The outline, or storyboard, for the commercial looked deceptively simple: four sketches and a few lines of 'voice-over.' Yet these few words and images (just enough to fill 15 seconds) had been carefully selected to convey crucial information about the product: its effectiveness in suppressing coughs and soothing sore throats, the absence of sugar, and its strawberry flavor. Turning this carefully calculated script into an effective commercial involved finding just the right actor: a young woman who would be attractive to the target audience and who could make her positive response to the cough drops look convincing. Forty-two actors were. auditioned; one was chosen. The actor wasn't the only element of the commercial that had to go through an audition. More than a hundred outfits were inspected before one was chosen for her to wear, and hundreds of strawberries had to be sorted through. The filming began at 9:30 one morning. "All" the actor had to do was to open a box of cough drops, pull out a strawberry and munch on it. Yet her movements and facial expressions had to be just right, and achieving that perfection took three hours and 72 shootings, or 'takes.' Even then—shooting completed—the job was far from done. Thousands of feet of film had to be reduced to a compact 45 feet of finished commercial. Using million-dollar, computerized equipment, the producer, writer, and art director selected the best two takes and mixed images and sound to produce a polished final product. The result? A simple, effortless-looking lisle film that shows none of the tremendous effort that went into producing it, but which should justify all of that time, creativity, and expense by boosting cough drop sales.

单选题Community cancer clusters are viewed quite differently by citizen activists than by epidemiologists. Environmentalists and concerned local residents, for instance, might immediately suspect environmental radiation as the culprit when a high incidence of cancer cases occurs near a nuclear facility. Epidemiologists, in contrast, would be more likely to say that the incidences were "inconclusive" or the result of pure chance. And when a breast cancer survivor, Lorraine Pace, mapped 20 breast cancer cases occurring in her West Islip, Long Island, community, her rudimentary research efforts were guided more by hope--that a specific environmental agent could be correlated with the cancers than by scientific method. When epidemiologists study clusters of cancer cases and other noncontagious conditions such as birth defects or miscarriage, they take several variables into account, such as background rate (the number of people affected in the general population), cluster size, and specificity (any notable characteristics of the individual affected in each case). If a cluster is both large and specific, it is easier for epidemiologists to assign blame. Not only must each variable he considered on its own, but it must also be combined with others. Lung cancer is very common in the general population. Yet when a huge number of cases turned up among World War Ⅱ shipbuilders who had all worked with asbestos, the size of the duster and the fact that the men had had similar occupational asbestos exposures enabled epidemiologists to assign blame to the fibrous mineral. Although several known carcinogens have been discovered through these kinds of occupational or medical clusters, only one community cancer cluster has ever been traced to an environmental cause. Health officials often discount a community’s suspicion of a common environmental cause because citizens tend to include cases that were diagnosed before the afflicted individuals moved into the neighborhood. Add to this the problem of cancer's latency. Unlike an infectious disease such as cholera, which is caused by a recent exposure to food or water contaminated with the cholera bacterium, cancer may have its roots in an exposure that occurred 10 to 20 years earlier. Do all these caveats mean that the hard work of Lorraine Pace and other community activists is for nothing? Not necessarily. Together with many other reports of breast cancer clusters on Long Island, the West Islip situation highlighted by Pace has helped epidemiologists lay the groundwork for a well designed scientific study.

单选题A full ______ of all the reasons for and against closing the railway has begun

单选题To survive in the intense trade competition between countries, companies must ______ the qualities and varieties of their products to the world-market demand.

单选题In 1995 Martin Luther King, Jr. gained national ______ for his nonviolent methods used in a bus boycott in Montgomery.

单选题Despite so many auspicious indicators, the America depicted in political and intellectual debate is invariably a place we should be building starships to flee. To the left, the United States remains a land of racial repression, corporate oligarchy, and environmental decay; to the right, a country where all things pure are collapsing. Such views hold considerable sway. Whitman's The Optimism Gap reports that 1996 polls showed that only 15 percent of Americans believe the country is getting better. In similar polls, about half said the nation is worse off compared to how it was when their parents were growing up, and 60 percent believed the United States in which their children dwell will be worse still. Though most Americans are today healthier, better housed, better fed, better paid, better educated, better defended, more free, and diverted by a cornucopia of new entertainment products and services, somehow they've managed to convince themselves their parents had it better during the Dust Bowl. As Robert Samuelson noted in his skillful book, the revolution of rising expectations has taken on a life of its own: "There can never be enough prosperity." Polls now suggest that, regardless of how much money an American has, he or she believes that twice as much is required. Samuelson further contends that one reason for all the unfocused anxiety is that the media have gotten so much better at emphasizing things to worry about. Tropical storms that might hit the United States get more network coverage than any favorable turn of events. Television crime coverage, especially, now seems itched to cause civic fright, while movies and network entertainment programming depict violence as far more pervasive than it actually is. As Christopher Jencks, a professor of government at Harvard University. Notes: "When I was growing up there was violence on TV, but it was cowboys having shootouts. I never worried that rustlers world come over the hill into my neighborhood. Now the violence on television is presented as if it's about to get you personally. Every screen you look, at home or in theaters, has something disastrous on it. No wonder people think the country is out of control."Conservative thinkers and politicians seem distressed by the contemporary milieu in part because Americans are more or less willingly adopting gender equality and cultural openness, including a culture in which minority writing and art are being admitted to the canon. The political and academic left can't stand the contemporary milieu in part because class war, economic breakdown, and environmental calamity seem less and less likely. "The left elites talk with obsessive negativism about the religious right because it's one of the few things they can find to still get upset about," notes Orlando Patterson of Harvard. "The right elite is similarly obsessive about the supposed culture war, when all the evidence is that the United States is becoming ever more tolerant and ever more at peace with diversity./

单选题Living in poverty, John sold for 500 dollars the ______ of his mother's first work which made her famous.(2004年上海理工大学考博试题)