单选题______ H(h)onesty is ______ bedrock of any healthy relationship. A．A; an B．A; × C．×; the D．×; ×

单选题"Oh Captain! My Captain!" is Whitman"s mourning poem to______.

单选题What is new in NASA's plan to return to the moon by 2018?

单选题 The growth of population during the past few centuries is no proof that population will continue to grow straight upward toward infinity and doom. On the contrary, demographic history offers evidence that population growth has not been at all constant. According to paleo-ecologist Edward Deevey, the past million years show three momentous changes. The first, a rapid increase in population around one million B. C., followed the innovations of tool-making and tool-using. But when the new power from the use of tools had been exploited, the rate of world population growth fell and became almost stable. The next rapid jump in population started perhaps 10,000 years ago, when men began to keep herds, plow and plant the earth. Once again when initial productivity gains had been absorbed, the rate of population growth abated. These two episodes suggest that the third great change, the present rapid growth, which began in the West between 250 and 350 years ago, may also slow down when, or if technology begins to yield fewer innovations. Of course, the current knowledge revolution may continue without foreseeable end. Either way contrary to popular belief in constant geometric growth--population can be expected in the long nm to adjust to productivity.

单选题Neither of us ______ the experience of studying abroad. A．has B．have C．having D．are having

单选题Got milk? Be very afraid. Or, preferably, a bit skeptical. Some folks are about to try to convince you that milk is toxic. But the real question is, what"s more dangerous to your health: milk, or celebrities and activists embarked on the latest trendy crusade (改革)? This month marks the publicity-pumped debut of the Anti Dairy Coalition, a band of physicians, self-described "Holly-wood personalities" and others who decry what they call "the health and nutritional risks of consuming dairy products". The coalition, including its spokes-Jeremiah, writer George Plimpton, would have you believe that milk causes heart disease, cancer infections, asthma, allergies and tuberculosis. Robert Cohen, founder of the ADC (and author of Milk: The Deadly Poison , writes: "The Fountain of Youth and cure to illness can be obtained by giving up milk." Hyperbole aside, the ADC is spotlighting a question hotly debated by everyone from nutritionists to parents. Many patients ask doctors whether they should give up milk, like that supermodel they saw interviewed on TV. And to be sure, the ADC"s overwrought claims do have some scientific basis. Take heart disease. Foods like butter, cheese, ice cream and whole milk are packed with saturated fat (饱和脂肪), which blocks arteries (动脉) and can lead to heart attacks. That"s why most nutritionists advise switching to low-fat or skim milk and eating more yogurt and cottage cheese than Haagen-Dazs and Bric. Even skim milk, though, can trigger allergies in some people, including infants, who in any case will get more iron and other key nutrients from breast milk or formula. So must you flee from milk entirely? Yes, says Cohen, who holds that skim milk is the devil"s brew. It"s full of—are you sitting down?—protein. And here"s where the ADC starts twisting the facts to reach wild conclusions. Allergies are frequently triggered by proteins (true; asthma is an allergic condition (true; it"s been increasing dramatically (true; doctors don"t know the cause (true; therefore, the protein in milk must be the culprit (罪魁祸首)? A similar leap of illogic assumes that because women in the Netherlands. Denmark, Norway and Sweden consume lots of milk and also suffer high rates of breast cancer, the former must cause the latter. Another clunker is Cohen"s claim that widespread lactose intolerance (乳糖不耐受)—the inability to digest dairy products—means milk is of little use as a source of calcium. In fact, many cases of lactose intolerance are mild and interfere only slightly with calcium uptake. Many people intolerant of milk can easily digest yogurt. And lactase tablets (乳糖分解酵素片) can make dairy products digestible even in severe cases. If milk isn"t the perfect food, it"s still got some big things going for it. It"s an inexpensive source of calcium, protein, potassium and other vitamins and minerals. And unlike other sources of calcium, such as, say, steamed kale, milk is a food kids will eat. The ADC feels that milk is the root of most human maladies (疾病), but I can point to other single-issue obsessive who insist the villain is meat or wheat or sugar or some other substance that our species has long and happily consumed. I often learn something by examining their claims. But I keep coming back to the mainstream nutritionists, who emphasize a balanced diet and advise moderation in all things.

单选题Sleep is divided into periods of so-called REM sleep, characterized by rapid eye movements and dreaming, and longer periods of non-REM sleep.【C1】______ kind of sleep is at all well-understood, but REM sleep is【C2】______ to serve some restorative function of the brain. The purpose of non-REM sleep is even more【C3】______ . The new experiments, such as those【C4】______ for the first time at a recent meeting of the Society for Sleep Research in Minneapolis, suggest fascinating explanations【C5】______ of non-REM sleep. For example, it has long been known that total sleep【C6】______ is 100 percent fatal to rats, yet,【C7】______ examination of the dead bodies, the animals look completely normal. A researcher has now【C8】______ the mystery of why the animals die. The rats【C9】______ bacterial infections of the blood,【C10】______ their immune systems—the self-protecting mechanism against disease—had crashed.

单选题You shouldyour stupid ideas, otherwise you'll regret in the future. A. put down B. put away C. put aside D. put out

单选题______ is now one of the two official languages in New Zealand.

单选题This article mainly refers to ______.

单选题A. trueB. tuneC. fluteD. June

单选题卓别林主演的电影有( )。

单选题But that he came to help me, I______. A. can't but succeed B. could not have succeeded C. couldn't succeed D. didn't succeeded

单选题The original elections were declared ______by the former military ruler.(2013年北京航空大学考博试题)

单选题{{B}}Passage Four{{/B}} A recent history of the Chicago meat-packing industry and its workers examines how the industry grew from its appearance in the 1830's through the early 1890's. Meat-packers, the author argues, had good wages, working conditions, and prospects for advancement within the packinghouses, and did not cooperate with labor agitators since labor relations were so harmonious. Because the history maintains that conditions were above standard for the era, the frequency of labor disputes, especially in the mid-1880's, is not accounted for. The work ignores the fact that the 1880's were crucial years in American labor history, and that the packinghouse workers! efforts were part of the national movement for labor reform. In fact, other historical sources for the late nineteenth century record deteriorating housing and high disease and infant mortality rates in the industrial community, due to low wages and unhealthy working conditions. Additional date from the University of Chicago suggest that the packing houses were dangerous places to work. The government investigations commissioned by President Theodore Roosevelt which eventually led to the adoption of the 1906 Meat Inspection Act found the packinghouses unsanitary, while observed that most of the workers were poorly paid and overworked. The history may be too optimistic because most of its data date from the 1880's at the latest, and the information provided from that decade is insufficiently analyzed. Conditions actually declined in the 1880's, and continued to decline after the 1880's, due to are organization of the packing process and a massive influx of unskilled workers. The deterioration. In worker status, partly a result of the new availability of unskilled and hence cheap labor, is not discussed. Though a detailed account of work in the packing-houses is attempted, the author fails to distinguish between the wages and conditions for skilled workers and for those unskilled laborers who comprised the majority of the industry's workers from the 1880's on. While conditions for the former were arguably tolerable due to the strategic importance of skilled workers in the complicated slaughtering, cutting and packing process (though worker complaints about the rate and conditions of work were frequefit), pay and conditions for the latter were wretched. The author's misinterpretation of the origins of the feelings the meat-packers had for their industrial neighborhood may account for the history's faulty generalizations. The pride and contentment the author remarks upon were, arguably, less the products of the industrial world of the packers--the giant yards and the intricate plants--than of the unity and vibrancy of the ethnic cultures that formed a viable community on Chicago's South Side. Indeed, the strength of this community succeeded in generating a social movement that effectively confronted the problems of the industry that provided its livelihood.

单选题In order to strengthen both the forearm and the grip, many athletes will repeatedly squeeze a tennis ball in their hands.