单选题Designers generally have the area Uconstructed/U so that the waste goes out in stages.

单选题{{B}}第三篇{{/B}} {{B}}Computers in Cars{{/B}} You're far from home on a lonely road. Shadowy forests stretch away on both sides. A thick mist (雾) makes it difficult to see far beyond your car's windshield (挡风玻璃). "Can this be route 90A?" you wonder. If it is, you should be near a town. Yet there's no hint of one. Night is closing in, and you're low on gasoline. This is a situation where an in-car computer that can navigate would be a big help. A car computer that navigates? Yes! Such computers exists. Several experimental models are being tested by General Motors, Ford, Chrysler, and several foreign car markets. These computers vary in details. But they all contain series of maps on Vediodiscs or videotapes. For example, one computer system contains 13,300 maps covering the continental US. Before starting out on a trip, a driver can type in the code for the region he or she plans to drive through. The computer then shows a map of that region. At the same time, a tiny radio receiver linked to the computer goes to work. It picks up signals from navigation satellites such as the NAVSTAR network. Using these signals, the computer shows a the car's position at all times and displays this position on the map. The computer can also calculate and display the best route to follow. A navigation computer may also receive and use data about road construction, weather conditions, and traffic jams. This information would be displayed to the driver and the computer would also use the information to work out alternate (交替的) routes. Most cars nowadays also contain computers that help cars run more effic!ently. Microprocessors (微处理机的) control certain engine functions by regulating the mixing of fuel. Data on car speed, oil pressure, revolutions per minute, engine temperature, and fuel level' can be displayed as digital data (numbers) or warming lights. Some auto designers suggest that a central computer display can be used to clearly present such timely information as car speed and fuel level. Warning lights would indicate a drop in oil pressure or a sudden rise in engine temperature. To get more information on these conditions, the driver would call it up on the computer display screen. When needed, the computer could be "asked" to provide navigation aid or information about the car's condition.

单选题It is hard for me to give you a {{U}}definite{{/U}} answer.

单选题A beautiful woman attended to me in that store yesterday.A. waited onB. talked toC. spoke toD. stayed With

单选题 Pushbike Danger Low speed bicycle crashes can badly injure -- or even kill -- children if they fall onto the ends of the handlebars (车把). So a team of engineers is redesigning it to make it safer. Kristy Arbogast, a bioengineer at the Children's Hospital of Philadelphia in Pennsylvania, began the project with her colleagues. The cases they reviewed about serious abdominal (腹部的) injuries in children in the past 30 years showed that more than a third were caused by bicycle accidents, "The task was to identify how the injuries occurred and come up with some countermeasures," she says. By interviewing the children and their parents, Arbogast and her team were able to reconstruct many of the accidents and identified a common cause for serious injuries. They discovered that most cases occur when children hit an obstacle at slow speed, causing them to topple (摇摆) over. To maintain their balance the children turn the handlebars through 90 degrees -- but their momentum (冲力) forces them into the end of the handlebars. The bike then falls over and the other end of the handlebars hits the ground, pushing it into their abdomen (腹部). The solution the group came up with is a handgrip (握柄) fitted with a spring and damping (减速) system. The spring absorbs up to 50 per cent of the forces transmitted (传递) through the handlebars in an impact. The group hopes to commercialize the device, which should add only a few dollars to the cost of a bike. "But our task has been one of education because up until now, bicycle manufacturers were unaware of the problem," says Arbogast.

单选题Her sister urged her to apply for the job.

单选题Alice trusts you, only you can persuade her to give up the foolish idea.

单选题The future {{U}}survival{{/U}} of the bald eagle is still an important American ecological concern.

单选题Some Things We Know about Language Many things about language are a mystery, and many will always remain so. But some things we do know. First, we know that all human beings have a language of some sort. There is no race (种族) of men anywhere on earth so backward that it has no language, no set of speech sounds by which the people communicate with one another. Furthermore, in historical times, there has never been a race of men without a language. Second, there is no such thing as a primitive (原始的) language. There are many people whose cultures are undeveloped, who are, as we say, uncivilized, but the languages they speak are not primitive. In all known languages we can see complexities that must have been tens of thousands of years in developing. This has not always been well understood; indeed, the direct contrary has often been stated. Popular ideas of the language of the American Indians will illustrate. Many people have supposed that the Indians communicated in a very primitive system of noises. Study has proved this to be nonsense. There are, or were, hundreds of American Indian languages, and all of them turn out to be very complicated and very old. They are certainly different from the languages that most of us are familiar with, but they are no more primitive than English and Greek. A third thing we know about language is that all languages are perfectly adequate. That is, each one is a perfect means of expressing the culture of the people who speak the language. Finally, we know that language changes. It is natural and normal for language to change; the only languages which do not change are the dead ones. This is easy to understand if we look backward in time. Change goes on in all aspects of language. Grammatical features change as do speech sounds, and changes in vocabulary are sometimes very extensive and may occur very rapidly. Vocabulary is the least stable part of any language.

单选题There is always excitement at the Olympic Games when an athlete breaks a previous performance.A. beatsB. matchesC. maintainsD. announces

单选题The police believe the motive for the murder was jealousy.A. choiceB. ideaC. decisionD. reason

单选题Image Martian Dust Particles NASA"s Phoenix Mars Lander has taken its first ever picture of a single particle of rusty Martian dust with one of its microscopes. The dust particles of dust were shown at a higher magnification than anything outside of Earth that has been imaged before. The rounded particle measured only about one micrometer, or one millionth of a meter, across. "Taking this image required the highest resolution microscope operated off Earth and a specially designed device to hold the Martian dust," said Tom Pike, a Phoenix science team member from Imperial College London. "We always knew it was going to be technically very challenging to image particles this small." The device that imaged the dust speck is called an atomic force microscope, which maps the shape of particles in three dimensions by scanning them with a sharp tip at the end of a spring. The atomic force microscope can detail the shapes of particles as small as about 100 nanometers. And this won"t be the last dust particle that Phoenix will image. "After this first success, we"re now working on building up a portrait gallery of the dust on Mars," Pike said. Dust exists everywhere on Mars, coating the surface and giving it its rusty red color. Dust particles also color the Martian sky pink and feed storms that regularly envelope the planet. The ultrafine dust is the medium that actively links gases in the Martian atmosphere to processes in Martian soil, so it is critically important to understanding Mars" environment, the researchers said. The $ 420-million Phoenix mission is analyzing the dust and subsurface ice layers of Mars" arctic regions to look for signs of potential past habitability. The particle seen in the atomic force microscope image was part of a sample scooped by the robotic arm from the "Snow White" trench and delivered to Phoenix"s microscope station in early July.

单选题Honesty is the best policy, as the English saying goes. Unfortunately, honesty often deserts us when nobody is watching, British psychologists reported last week. Researchers at UK's Newcastle University set up an experiment in their psychology department's coffee room. They set a kettle, with tea, coffee and milk on the counter and hung up a sign listing the price for drinks. People helping themselves to a cup of tea or coffee were supposed to put a few cents into a box nearby. The scientists hung a poster above the money box and alternated each week between images of gazing eyes and pictures of flowers. The researchers found that staff paid 2.76 times more for their drinks when the image of the eyes was hung. "Frankly we were shocked by the size of the effect," said Gilbert Roberts, one of the researchers. Eyes are known to be a powerful perceptual signal for humans, scientists say. "Even though the eyes were not real, they still seemed to make people behave more honestly," said the leader of the study. Researchers believe the effect throws light on our evolutionary past. It may arise from behavioral traits that developed when early humans formed social groups to strengthen their chances of survival. For social groups to work, individuals had to cooperate, rather than act selfishly. "There's an argument that if nobody is watching us, it is in our interests to behave selfishly. But when we are being watched we should behave better. So people see us as co-operative and behave the same way towards us," one scientist said. The new finding indicates that people have striking response to eyes. That might be because eyes and faces send a strong biological signal we have evolved to respond to. The finding can be put to practical use. For example, images of eyes could boost ticket sales on public transport and improve surveillance systems to prevent antisocial behavior. The main idea of the passage is thatA. humans have a stronger response to eyes than to flowers.B. photos of human eyes have a positive effect on people's behavior.C. the scientists' new finding may have many practical uses.D. people may behave dishonestly when there's no one aroun

单选题Please do not hesitate to call me if I can be of further assistance.

单选题The writer's advice about alcohol before you make a speech is to take one or two drinks so as to give yourself some confidence.

单选题第二篇 Driven to Distraction Joe Coyne slides into the driver"s seat, starts up the car and heads to town. The empty stretch of interstate gives way to urban congestion, and Coyne hits the brakes as a pedestrian suddenly crosses the street in front of him. But even if he hadn"t stopped in time, the woman would have been safe. She isn"t real. Neither is the town. And Coyne isn"t really driving. Coyne is demonstrating a computerized driving simulator that is helping researchers at Old Dominion University (ODU) examine how in vehicle guidance systems affect the person behind the wheel. The researchers want to know if such systems, which give audible or written directions, are too distracting—or whether any distractions are offset by the benefits drivers get from having help finding their way in unfamiliar locations. "We are looking at the performance and mental workload of drivers," said Cary Baldwin, the assistant psychology professor leading the research, which involves measuring drivers" reaction time and brain activity as they respond to auditory and visual cues. The researchers just completed a study of the mental workload involved in driving through different kinds of environments and heavy, light traffic. Preliminary results show that as people "get into more challenging driving situations, they don"t have any extra mental energy to respond to something else in the environment." Baldwin said. But the tradeoffs could be worth it, she said. The next step is to test different ways of giving drivers navigational information and how those methods change the drivers" mental workload. "Is it best if they see a picture.., that shows their position, a map kind of display?" Baldwin said. "Is it best if they hear it?" Navigational systems now on the market give point by point directions that follow a prescribed route. "They"re very unforgiving" Baldwin said. "If you miss a turn, they can almost seem to get angry." That style of directions also can be frustrating for people who prefer more general instructions. But such broad directions can confuse drivers who prefer route directions. Baldwin said. Perhaps manufacturers should allow drivers to choose the style of directions they want, or modify systems to present some information in a way that makes sense for people who prefer the survey style, she said. Interestingly, other research has shown that about 60 percent of men prefer the survey style, while 60 percent women prefer the route style, Baldwin said. This explains the classic little thing of why men don"t like to stop and ask for directions and women do, Baldwin added.

单选题His speech was a powerful spur to action.

单选题It is Unormal/U for a teacher to get angry with the student who repeats the same mistake.

单选题The photographs Uevoked/U memories of our

单选题Exposure to the Sun can accelerate the ageing process.