单选题We have got to abide by the rules.

单选题Her treatment of the subject is {{U}}exhaustive{{/U}}.

单选题Living alone in a house, the writer seems to

单选题When money was needed for flood relief or to build dams, the money had to come from the federal government, since there were no local funds to Umake use of/U.

单选题Denny His nickname is Denny. He weighs 400 pounds; he is fearless and he never goes to sleep on the job. An ideal security guard? For many situations he may be. And if he"s so good that you wish you had a dozen like him, just place your order. Denny is a robot guard. Denny can detect, within a 150-foot radius, the presence of anything or anybody that shouldn"t be there. Its swiveling (旋转) head contains microwave and infrared sensors that can detect people as well as smoke. In future editions the head will also contain sensors that can smell the weak smell of a human body. A high-resolution TV camera in Denny"s head is on at all time. When something unexpected comes into view, the TV transmitter switches on. Thus the human overseer (看管人) in the control center sees the sudden appearance of a picture on the monitor screen. At the same time the picture is automatically videotaped. Normal speed of the robot guards is about one mile an hour, and they can even talk: "you have been detected," warns the voice from the clever guard. Denny is designed to patrol corridors and other areas after lock-down hours (of course, he can work round the clock when necessary), not to move among people. If, say, a prisoner does get near the corridor where he should not be, it"ll immediately tell its base station by radio. Denny has understandable limitations. He can"t open doors or watch stairs, for example, or distinguish a friend from an enemy. Thus he will have to go about unarmed. And he won"t be able to replace human security guards where people move about freely.

单选题{{B}}第三篇{{/B}} Too Little for Global Warming Oil and gas will run out too fast for doomsday global warming scenarios to materialize, according to a controversial new analysis presented this week at the University of Uppsala in Sweden. The authors warn that all the fuel will be burnt before there is enough carbon dioxide in the atmosphere to realize predictions of melting ice caps and searing temperatures. Defending their predictions, scientists from the Intergovernmental Panel on Climate Change say they considered a range of estimates of oil and gas reserves, and point out that coal-burning could easily make up the shortfall. But all agree that burning coal would be even worse for the planet. The IPCC's predictions of global meltdown pushed forward the 1997 Kyoto Protocol, an agreement obliging signatory nations to cut CO2 emissions. The IPCC considered a range of future scenarios, from unlimited burning of fossil-fuels to a fast transition towards greener energy sources. But geologists Anders Sivertsson, Kjell Aleklett and Colin Campbell of Uppsala University say there is not enough oil and gas left even the most conservative of the 40 IPCC scenarios to come to pass. Although estimates of oil and gas reserves vary widely, the researchers are part of a growing group of experts who believe that oil supplies will peak as soon as 2010, and gas soon after. Their analysis suggests that oil and gas reserves combined about to the equivalent of about 3,500 billion barrels of oil considerably less than the 5,000 billion barrels estimated in the most optimistic model envisaged by the IPCC. Even the average forecast of about 8,000 billion barrels is more than twice the Swedish estimate of the world's remaining reserves. Nebojsa Nakicenovic, an energy economist at the University of Vienna, Austria who headed the 80-strong IPCC team that produced the forecasts, says the panel's work still stands. He says they factored in a much broader and internationally accepted range of oil and gas estimates than the "conservative" Swedes. Even if oil and gas run out, "there's a huge amount of coal underground that could be exploited", he says that burning coal could make the IPCC scenarios come true, but points out that such a switch would be disastrous. Coal is dirtier than oil and gas and produces more CO2 for each unit of energy, as well as releasing large amounts of particulates. He says the latest analysis is a "shot across the bows" for policy makers.

单选题The weather is a constant subject of conversation in Britain.

单选题The Moon and most artificial satellites travel around the Earth in elliptical paths .

单选题The Issue of Package Maybe everyone has such an experience that you have to unwrap several layers of packaging when you enjoy a piece of candy. But this overuse of wrapping is not confined to luxuries. It is becoming increasingly difficult to buy anything that is not done up in beautiful wrapping. The package itself is of no interest to the shopper, who usually throws it away immediately. So why is it done? Some of it, like the cellophane on meat, is necessary, but most of the rest is simply competitive selling. This is absurd. Packaging is using up scarce energy and resources and messing up the environment. Recycling is already happening with milk bottles which are returned to the dairies, washed out, and refilled. But both glass and paper are being threatened by the growing use of plastic. More dairies are experimenting with plastic bottles. The trouble with plastic is that it does not rot. Some environmentalists argue that the only solution to the problem of ever increasing plastic containers is to do away with plastic altogether in the shops, a suggestion unacceptable to many manufacturers who say there is no alternative to their handy plastic packs. It is evident that more research is needed into the recovery and reuse of various materials and into the cost of collecting and recycling containers as opposed to producing new ones. Unnecessary packaging, intended to be used just once, and make things look better so more people will buy them, is clearly becoming increasingly absurd. But it is not so much a question of doing away with packaging as using it sensibly. What is needed now is a more advanced approach to using scarce resources for what is, after all, a relatively unimportant function.

单选题To tell you the truth, I did extract several passages from the speech when writing my speech.A. take outB. take offC. take onD. take up

单选题{{B}}第三篇{{/B}} {{B}} Advice of a Writer{{/B}} Many a young person tells me he wants to be a writer. I always encourage such people, but I also explain that there's a big difference between "being a writer" and writing. In most cases these individuals are dreaming of wealth and fame, not the long hours alone at a typewriter. "You've got to want to write, I say to them, "not want to be a writer." The reality is that writing is a lonely, private and poor--paying affair. For every writer kissed by fortune there are thousands more whose longing is never rewarded. When I left a 20 _year career in the U. S. Coast Guard to become a freelance writer (自由撰稿者), I had no prospects at all: What I did have was a friend who found me my room in a New York apartment building. It didn't even matter that it was cold and had no bathroom. I immediately bought a used manual typewriter and felt like a genuine writer. After a year or so, however, I still hadn't gotten a break and began to doubt myself. It was so hard to sell a story that barely made enough to eat. But I knew I wanted to write. I had dreamed about it for years. I wasn't going to be one of those people who die wondering, What if? I would keep putting my dream to the test--even though it meant living with uncertainty and fear of failure. This is the Shadowland of hope, and anyone with a dream must learn to live there.

单选题The Science of the Future Until recently, the "science of the future" was supposed to be electronics and artificial intelligence. Today it seems more and more likely that the next great breakthroughs in technology will be brought through a combination of those two sciences with organic chemistry and genetic engineering. This combination is the science of biotechnology. Organic chemistry enables us to produce marvelous synthetic (合成的) materials. However, it is still difficult to manufacture anything that has the capacity of wool to conserve heat and also to absorb moisture. Nothing that we have been able to produce so far comes anywhere near the combination of strength, lightness and flexibility that we find in the bodies of ordinary insects. Nevertheless, scientists in the laboratory have already succeeded in "growing" a material that has many of the characteristics of human skin. The next step may well be "biotech hearts and eyes" which can replace diseased organs in human beings. These will not be rejected by the body, as is the case with organs from humans. The application of biotechnology to energy production seems even more promising. In 1996 the famous science-fiction writer, Arthur C. Clarke, many of whose previous predictions have come true. He said that we may soon be able to develop remarkably cheap and renewable sources of energy. Some of these power sources will be biological. Clarke and others have warned us repeatedly that sooner or later we will have to give up our dependence on non-renewable power sources. Coal, oil and gas are indeed convenient. However, using them also means creating dangerously high levels of pollution. It will be impossible to meet the growing demand for energy without increasing that pollution to catastrophic (灾难性的) levels unless we develop power sources that are both cheaper and cleaner. It is attempting to think that biotechnology or some other "science of the future" can solve our problems. Before we surrender to that temptation we should remember nuclear power. Only a few generations ago it seemed to promise limitless, cheap and safe energy. Today those promises lie buried in a concrete grave in a place called Chernobyl, in the Ukraine. Biotechnology is unlikely, however, to break its promises in quite the same or such a dangerous way.

单选题They have the capability to destroy the enemy in a few days.

单选题The Greatest Mystery of Whales The whale is a mammal-warm-blooded, air-breathing, giving birth to its young alive. sucking them-and, like all mammals, originated on land. There are many signs of this. Its front flippers (鳍足), used for steering and stability, are traces of feet. Immense strength is built into the great body of the big whales, and in fact most of a whale's body is one gigantic muscle. The blue whale's pulling strength has been estimated at 400 horsepower. One specimen was reported to have towed (牵引) a whaling vessel for seven hours at the rate of eight knots. An enraged whale will attack a ship. A famous example of this was the fate of whaler Essex, which was sunk off the coast South America early in the last century. More recently, steel ships have had their plates buckled in the same way. Sperm whales were known to seize the old-time whaleboats in their jaws and crush them. The greatest mystery of whales is their diving ability. The sperm whale can dive on the bottom for his favorite food, the octopus. In that search he is known to go as far down as 3,200 feet, where the pressure is 1,400 pounds, to the square inch. Doing so he will remain submerged as long as one hour. Two feats(壮举) are involved in this: storing up enough oxygen (all whales are air-breathed) and withstanding the great change in pressure. Just how he does it scientists have not determined. It is believed that some of the oxygen is stored in a special system of blood vessels, rather than just held in the lungs. And it is believed that a special kind of oil in his head is some sort of compensating mechanism that automatically adjusts the internal pressure of his body. But since you can't bring a live whale into the laboratory for study, no one knows just how these things work.

单选题He denies involvement with either drugs or the CIA.

单选题We can take control aggressively of the way we age and delay body Udeterioration/U that causes activities to be severely limited.

单选题A young man is being hailed a hero tonight after rescuing two children.A. reportedB. praisedC. provedD. caught

单选题1. Digital Realm In the digital realm the next big advance will be voice recognition. The rudiments are already here but in primitive form. Ask a computer to "recognize speech," and it is likely to think you want it to "wreck a nice beach." But in a decade or so we'll be able to chat away and machines will soak it all in. Microchips will be truly embedded in our lives when we can talk to them. Not only to ourcomputers; we'll also able to chat our automobile navigation systems, telephone consoles, browsers, thermostats, VCRs, microwaves and any other devices we want to boss around. That will open the way to the next phase of the digital age: artificial intelligence. By our providing so many thoughts and preferences to our machines each day, they'll accumulate enough information about how we think so that they'll be able to mimic our minds and act as our agents. Scary, huh? But potentially quite useful. At least until they don't need us anymore and start building even smarter machines they can boss around. The law powering the digital age up until now has been Gordon Moore's: that microchips will double in power and halve in price every 18 months or so. Bill Gates rules because early on he acted on the assumption that computing power—the capacity of microprocessors and memory chips—would become nearly flee; his company kept churning out more and more lines of complex software to make use of the cheap bounty. The law that will power the next few decades is that the bandwidth (the capacity of fiber-optic and other pipelines to carry digital communications) will become nearly free. Along with the recent advances in digital switching and storage technologies, this means a future in which all forms of content—movies, music, shows, books, data, magazines, newspapers, your aunt's recipes and home videos—will be instantly available anywhere on demand. Anyone will be able to be a producer of any content; you'll be able to create a movie or magazine, make it available to the world and charge for it, just like Time Warner! The result will be a transition from a mass. market world to a personalized one. Instead of centralized factories and studios that distribute or broadcast the same product to millions, technology is already allowing products to be tailored to each user You call subscribe to news sources that serve up only topics and opinions that fit your fancy. Everything from shoes to steel can be customized to meet individual wishes.

单选题The great changes of the city (astonished) every visitor to that city．

单选题Finding a job can be depressing and disappointing, and therefore it is important that you are prepared.A. exploitingB. frustratingC. profitingD. misleading