单选题When the weather is hot, you go to a lake or an ocean. When you are near a lake or an ocean, you feel cool .Why? The sun makes the earth hot, but it cannot make the water very hot. Although the air over the earth becomes hot, the air over the water stays cool. The hot air over the earth rises. Then the cool air over the water moves in and takes the place of the hot air. When you are near a lake or an ocean, you feel the cool air when it moves in. You feel the wind. And the wind makes you cool. Of course, scientists cannot answer all of your questions. If we ask, "why is the ocean full of salt?" Scientists will say that the salt comes from rocks. When a rock gets very hot or very cold, it cracks. Rain falls into the cracks. The rain then carries the salt into the earth and then into the rivers. The rivers carry the salt into the ocean. But then we ask, "what happens to the salt in the ocean? The ocean does not get more salty every year." Scientists are not sure about the answer to this question. We know a lot about our world. But there are still many answers that we do not have, and we are curious.

单选题Talks on climate change resumed in the German city of Bonn on July 16 to ______ global warming.

单选题Normally a student must attend a certain number of courses in order to graduate, and each course which he attends gives him a credit which he may count towards a degree. In many American universities the total work for a degree consists of thirty six courses each lasting for one semester. A typical course consists of three classes per week for fifteen weeks; while attending a university a student will probably attend four or five courses during each semester. Normally a student would expect to take four years attending two semesters each year. It is possible to spread the period of work for the degree over a longer period. It is also possible for a student to move between one university and another during his degree course, though this is not in fact done as a regular practice. For every course that he follows a student is given a grade, which is recorded and available for the student to show to prospective employers. All this imposes a constant pressure and strain of work, but in spite of this some students still find time for great activity in student affairs. Elections to positions in student organizations arouse much enthusiasm. The effective work of maintaining discipline is usually performed by students who advise the academic authorities. Any student who is thought to have broken the rules, for example, by cheating, has to appear before a student court. With the enormous numbers of students, the operation of the system does involve a certain amount of activity. A student who has held one of these positions of authority is much respected and it will be of benefit to him later in his career.

单选题Virtually everything astronomers know about objects outside the solar system is based on the detection of photons-quanta of electromagnetic radiation. Yet there is another form of radiation that permeates the universe: neutrinos. With (as its name implies) no electric charge, and negligible mass, the neutrino interacts with other particles so rarely that a neutrino can cross the entire universe, even traversing substantial aggregations of matter, without being absorbed or even deflected. Neutrinos can thus escape from regions of space where light and other kinds of electromagnetic radiation are blocked by matter. Not a single, validated observation of an extraterrestrial neutrino has so far been produced despite the construction of a string of elaborate observatories, mounted on the earth from Southern India to Utah to South Africa. However, the detection of extraterrestrial neutrinos are of great significance in the study of astronomy. Neutrinos carry with Their information about the site and circumstances of their production; therefore, the detection of cosmic neutrinos could provide new information about a wide variety of cosmic phenomena and about the history of the universe. How can scientists detect a particle that interacts so infrequently with other matter? Twenty-five years passed between Pauli's hypothesis that the neutrino existed and its actual detection; since then virtually all research with neutrinos has been with neutrinos created artificially in large particle accelerators and studied under neutrino microscopes. But a neutrino telescope, capable of detecting cosmic neutrinos, is difficult to construct. No apparatus can detect neutrinos unless it is extremely massive, because great mass is synonymous with huge numbers of nucleons (neutrons and protons), and the more massive the detector, the greater the probability of one of its nucleon's reacting with a neutrino. In addition, the apparatus must be sufficiently shielded from the interfering effects of other particles. Fortunately, a group of astrophysicists has proposed a means of detecting cosmic neutrinos by harnessing the mass of the ocean. Named DUMAND, for Deep Underwater Muon and Neutrino Detector, the project calls for placing an array of light sensors at a depth of five kilometers under the ocean surface. The detecting medium is the sea water itself: when a neutrino interacts with a particle in an atom of seawater, the result is a cascade of electrically charged particles and a flash of light that can be detected by the sensors. The five kilometers of seawater above the sensors will shield them from the interfering effects of other high-energy particles raining down through the atmosphere. The strongest motivation for the DUMAND project is that it will exploit an important source of information about the universe. The extension of astronomy from visible light to radio waves to x-rays and gamma rays never failed to lead to the discovery of unusual objects such as radio galaxies, quasars, and pulsars. Each of these discoveries came as a surprise. Neutrino astronomy will doubtlessly bring its own share of surprises.

单选题He told us that John, as well as his brother, ______ coming to the party. A. is B. are C. were D. was

单选题Which of the following is NOT correct according to the third paragraph?

单选题The study of literary influence among women writers has frequently adopted a model of sororal or matrilineal sharing in an often explicitly stated contrast to Harold Bloom's well-established theory of the "anxiety of influence" besetting male writers. In Bloom's powerfully influential vision, that anxiety is posed as a kind of Freudian agon of sons against fathers, a struggle of self-definition through resistance and mastery. Feminist critics have generally agreed with the Bloomian model as applied to male authors but have demurred with respect to women writers, whom we have tended to see in familial terms. The model of a separate women's tradition in literature, its inner coherence maintained by resistance to male dominance, that was posited in the 1970s by Ellen Moers, Elaine Showalter, and Sandra M. Gilbert and Susan Gubar has been widely accepted. As Betsy Erkkila points out, these groundbreaking feminist critics may not have significantly challenged the Bloomian model as applied to women writers and women precursors, but they did at any rate establish their resistance to the masculine literary establishment and the masculine model of rivalry. Their successors and elaborators have argued forcefully that a women's tradition is constituted of a supportive community whose members welcome the all-too-rare voices of foremothers calling to them across the ages. Even the literary foremothers nearer at hand, according to this prevailing vision, have served as models for emulation rather than hegemonic powers to be challenged. Erkkila, for example, asks pointedly, "How useful is the Bloomian model when the poet attempts to define herself not in relation to her poetic fathers but in relation to her poetic mothers." Her answer (later modified because of greater complexity) is not very. A metaphor of motherhood and daughterhood has, in the words of Linda R. Williams's recent revisionist theory, "profoundly affected our reading of women's literary history." Citing Alice Walker's argument about nebulous forms of knowing in In Search of Our Mothers' Gardens, Luce Irigary's concept of connectedness ( "One doesn't stir without the other") and Helene Cixous's version of the authentic woman writer's writing of her mother's milk in "The Laugh of the Medusa," Williams calls for an interpretation of literary connectedness not as a revision of the Freudian and Bloomian system-which Erkkila, by retaining the familial language, has in a sense retained, but as a way "outside of an Oedipal dynamic" altogether. The revisionist views of Williams and Erkkila are useful corrections of the prevailing mode of feminist theories that "romanticize, maternalize, essentialize, and eternalize women writers and the relationships among them." Neither, however, asks if women writers may not sometimes exhibit, rather than either revise or escape, the Bloomian model of literary rivalry. It is a prospect, perhaps, that we would prefer not to entertain. But it is a prospect that, while clearly not typical, may be less atypical than feminist critics may have supposed in our times too idealizing and essentializing theories. An instance of such a female adoption (and adaptation) of the Bloomian model of male writers' anxiety is Katherine Anne Porter's anxious and artfully duplicitous essay on a literary elder sister, "Reflections on Willa Cather." Operating in the loosely narrative fashion that characterized not only Porter's nonfiction but her very mode of thought, the essay purports to pay retrospective tribute to one of the preeminent women writers of the early and mid-twentieth century, but in fact asserts Porter's own stature in the world of letters. In the story of her essay, the protagonist is not Cather, as one would expect from the title, but Porter herself. The essay is cast in a pervasive first-person mode in which the observing or commenting "I" becomes the active principle and its putative topic a passive reflector, a mirror reflecting Katherine Anne Porter.

单选题The statistical figures in that report are not ______. You should not refer to them. A. accurate B. fixed C. delicate D. rigid

单选题She was between two very fat women and felt extremely uneasy, ______.

单选题 A. league B. tongue C. guess D. guest

单选题Radiation occurs from three natural sources: radioactive material in the environment such as in soil, rock, or building materials; cosmic rays; and substances in the human body, such as radioactive potassium in bones and radioactive carbon in tissues. These natural sources account for an exposure of about 100 millirems a year for the average American. The Iargcst single source of man-made radiation is medical X rays, yet most scientists agree that hazards from this source are not as great as those from weapons test fallout, since strontium 90 and carbon 14 become incorporated into the body, hence delivering radiation for an entire life- time. The issue is, however, by no means uncontroversial; the last two decades have witnessed intensified examination and dispute about the effects of low-level radiation, beginning with the United Nations Scientific Committee on the Effects of Atomic Radiation, which reported in 1958: "Even the smallest amounts of radiation are liable to cause deleterious genetic and perhaps also somatic effects." A survey conducted in Britain confirmed that an abnormally high percentage of patients suffering from arthritis of the spine who had been treated with X rays contracted cancer. Another study revealed a high incidence of childhood cancer in eases where the mother had been given prenatal pelvic X rays. These studies have pointed to the need to reexamine the assumption that exposure to low-linear energy transfer presents only a minor risk. Recently, examination of the death certificates of former employees of a West Coast plant which produces plutonium for nuclear weapons revealed markedly higher rates for cancers of the pancreas, lung, bone marrow, and lymph systems than would have been expected in a normal population. While the National Academy of Sciences Committee attributes this difference to chemical or other environmental causes rather than radiation, other scientists maintain that any radiation expo- sure, no matter how small, leads to an increase in cancer risk. It is believed by some that a dose of one rem, if sustained over many generations, would lead to an increase of 1 percent in the number of serious genetic defects at birth, a possible increase of 1,000 disorders per million births. In the meantime, regulatory efforts have been disorganized, fragmented, inconsistent, and characterized by internecine strife and bureaucratic delays. A Senate report concluded that coordination of regulation among involved departments and agencies was not possible because of jurisdictional disputes and confusion. One federal agency has been unsuccessful in its efforts to obtain sufficient funding and manpower for the enforcement of existing radiation laws, and the chairperson of a panel especially created to develop a coordinated federal program has resigned.

单选题The shorter working week, longer holidays, earlier retirement, more sabbaticals, job sharing these and other ways of reducing the amount of time people spend on their jobs are certainly likely to spread.

单选题The ministry announced at a State Council Information Office press conference on August 11 that 47 medical teams, with 779 members, were in Zhouqu treating patients, sterilizing the environment and drinking water, and ensuring proper disposal of corpses.

单选题The children glanced ______ at the box of candy they were told not to touch.