单选题The phenomenon that Americans and British people pronounce some words differently can be interpreted in terms of______.

单选题Although dolphins sometimes swim singly or in pairs, they usually______in large herds, often numbering in the hundreds.

单选题The first writer who took the vernacular as a serious way of presenting reality after Mark Twain is______.

单选题All______of the world carry on breeding experiments to increase yield or to improve disease resistance.

单选题Although he has become rich, he is still very______of his money.

单选题I would appreciate it______you help me with my English.

单选题The process of word formation by shifting the word class to change the meaning of a word is called ______.

单选题A lie can travel half way around the world while the truth is putting on its shoes.

单选题Pronouns, prepositions, conjunctions and articles are all open class items. (清华2001研)

单选题______your request for an additional assistant, I can only say at this stage that this is being considered.

单选题The miserable fate of Enron"s employees A will be a landmark in business history, B one of those events C that everyone agrees D must never allow to happen again.

单选题In Benjamin Franklin"s The Autobiography, 13 virtues are enlisted for seek of self-discipline, which show representatively ______.

单选题I was stunned by her request for a letter of recommendation given our superficial knowledge of one another.

单选题Thanks to closed doors and fierce gatekeepers, bosses are tricky to observe in their natural habitat. Yet it might be useful to know what they do all day, and whether any of it benefits shareholders. A new Harvard Business School working paper sheds some light. Researchers asked the chief executives of 94 Italian firms to have their assistants record their activities for a week. You may take this with a grain of salt. Is the boss's assistant a neutral observer? If the boss spends his lunch hour boozing, or in a motel with his assistant, will she record this truthfully? Nonetheless, here are the results. The average Italian boss works for 48 hours a week and spends 60% of that time in meetings. The most diligent put in another 20 hours. And the longer they work, the better the company does. Less diligent chief executives are more likely to have one-to-one meetings with people from outside the company. The authors speculate that such people are trying to raise their own profile, perhaps to secure a better job. Bosses who work longer hours, by contrast, spend more of them meeting their own employees. Bosses often complain that they get bogged down in day-to-day operations, says Rajesh Chandy, a professor at the London Business School. Regulations that make them legally responsible for their underlings' wrongdoings are partly to blame. The prospect of jail is a powerful attention-grabber. Many bosses also feel they must dash around the world pitching to clients. Jim Hagemann Snabe, co-chief executive of SAP, a software firm, reckons that he met over 200 last year. Mr. Chandy thinks bosses should spend less time with clients and more time thinking about the future. How much time they spend thinking about anything is hard to measure. But in an experiment, Mr. Chandy measured how often bosses use forward-looking words like "will" and "shall" in their public statements. He concluded that bosses spend only 3 -4% of their day thinking about long-term strategy. Brian Sullivan, the chief executive of CTPartners, a headhunting firm, says the most difficult part of his job is saying no to people who want a piece of his time. "If it was up to our partners I would be at every pitch, " he says. Mr. Sullivan says the only time he gets for blue-sky thinking is when he is in the sky. "Chief executives will rue the day when BlackBerrys work on planes, " he predicts. Bill Gates took regular "think weeks" , when he would sit alone in a cabin for 18 hours a day reading and contemplating. This, it is said, led to such strategic masterstrokes as "the internet tidal wave memo" in 1995, which shifted Microsoft's focus(some say belatedly)to the web. But not every boss thinks he needs more time for thinking. "You can hire McKinsey to do that for you, " says one.

单选题The following ideas about language are wrong EXCEPT______.

单选题Having finished their morning work, the clerks stood up behind their desks, ______ themselves.

单选题When varieties of language are classified in respect of their users, they are called registers.

单选题Read the following passage carefully and then decide whether the statements which follow are true(T)or false(F). Do Cell Phones Cause Cancer? There are safety-warning labels on cigarettes and alcohol. Now some groups are advocating that similar cautions be printed on cell phones. Recently, a bill in the Maine state senate proposed a label warning users, especially children and pregnant women, of the risks of brain cancer from electromagnetic radiation emanating from the device. But the Maine legislature voted down the bill in March, stating that the scientific evidence does not indicate a public health risk. Yet, the debate rages on. Can cell phones really cause cancer? Supporters of the Maine legislation argued that uncertainty about the long-term effects of cell phone radiation warranted public safety notices. They also pointed to a handful of European studies that linked brain and auditory nerve tumors with using cell phones for more than 10 years and at younger ages. "I think my short answer is that the evidence isn"t 100 percent, but there"s a strong indication that, yes, cell phone use does cause cancer(over a long period of time), " said David Carpenter, director of the Institute for Health and Environment at the University of Albany, and an advocate for the Maine bill on cell phone warnings. Carpenter points to a 2007 meta-analysis that associated ipsilateral auditory nerve tumors(acoustic neuromas)with people who had used cell phones for at least 10 years, as well as a 2009 Swedish study that found a heightened risk for brain tumors among people who had used cell phones for at least 10 years, especially for those under 20 years old. Not surprisingly, cell phone industry insiders disagree, " " The peer-reviewed scientific evidence has overwhelmingly indicated that wireless devices, within the(radiation)limits established by the FCC, do not pose a public health risk or cause any adverse health effects, " said John Walls, vice president of public affairs for CTIA—The Wireless Association, an international trade group that represents the wireless telecomm industry. For instance, 2001 Danish study and 2006 follow-up found no relationship between cancer risk and long-term cell phone use among more than 400, 000 users. In addition, a statistical review from the National Institutes of Cancer revealed no rise in cancer incidence rates from 1975 to 2005 in relation to the rise in cell phone usage. Joshua Muscat, a public health science professor at Pennsylvania State University who has studied the cancer-causing potential of cell phone radiation, also questions the connection. "There is no known mechanism by which radio frequency fields generated by cell phones can cause cancer because cell phone radiation is non-ionizing, " Muscat said. Nevertheless, when you press a cell phone against your ear while it"s in use, head and brain tissues can absorb that vibrating, low-frequency radiation and heat. Because of that radiation effect, the Federal Communications Commission(FCC)sets specific absorption rates(SARs)that dictate the maximum amount of radiation cell phones and mobile devices can give off. " The power output from these phones is extremely low, " Muscat told Discovery News. However, David Carpenter counters that the SARs don"t take into account the potential long-term damage of close-range exposure to heat-inducing radiation, especially in children. "Those(FCC)levels are set by engineers and physicists, and those aren"t the people who should be setting health-based standards, " he said. Carpenter thinks that the results from a large, 13-country study called Interphone, which consists of a series of 16 case-controlled studies conducted between 2000 and 2005, could finally settle the debate. Each of the Interphone studies recruited at least 100 people who had developed brain cancer or certain types of tumors, along with a healthy control group. But it"s been hampered by methodological shortcomings. In many cases, the group was asked to describe their cell phone habits, which critics contend led to recall bias. So far, it still hasn"t rendered a final verdict. For now, the National Cancer Institute, American Cancer Society, U.S. Food and Drug Administration, among other leading health agencies and organizations, aren"t ringing the alarm bells. For one thing, scientists have yet to pinpoint how the low-frequency cell phone radiation could cause cancer. "Cell phone radiation"s effect in the body appears to be insufficient to produce the genetic damage typically associated with developing cancer, " said Robert N. Hoover, director of epidemiology for the National Cancer Institute, in an official statement to Congress. " To date, no alternative mechanism about how this exposure might result in cancer has been vetted adequately. " Until scientists can unmask that " mechanism, " Carpenter urges consumers to play it safe and text message or hold cell phones away from their ears to limit radiation exposure. Even Muscat from Penn State leaves a space—albeit a narrow one—for caution. "It is a legitimate concern in the sense that there may be some unknown, undiscovered mechanism that could be promoting the development of cancer, " Muscat said. "This seems unlikely, but if one looks at other scientific disciplines such as cosmology or particle physics, there are often paradigm shifts that occur with new discoveries. "

单选题The bus moved slowly in the thick fog. We arrived at our______almost two hours later.

单选题"Wife", which used to refer to any woman, stands for "a married woman" in modern English. This phenomenon is known as______. (西安交大2008研)