单选题 Motoring Technology 1
单选题2. The new garment fits her perfectly.
单选题11. The steadily rising cost of labor on the waterfront has greatly increased the cost of shipping cargo by water.
单选题. The Need to Remember Some people say they have no memory at all: "I just can't remember a thing!" But of course we all have a memory. Our memory tells us who we are. Our memory helps us to make use in the present of what we have learnt in the past. In fact we have different types of memory. For example, our visual memory helps us recall facts and places. Some people have such a strong visual memory, they can remember exactly what they have seen, for example, pages of a book, as a complete picture. Our verbal (言语的) memory helps us remember words and figures we may have heard but not seen or written: items of a shopping list, a chemical formula, dates, or a recipe. With our emotional (情感的) memory, we recall situations or places where we had strong feelings, perhaps of happiness or unhappiness. We also have special memories for smell, taste, touch and sound, and for performing physical movements. We have two ways of storing any of these memories: Our short-term memory stores items for up to thirty seconds—enough to remember a telephone number while we dial. Our long-term memory, on the other hand, may store items for a lifetime. Older people in fact have a much better long-term memory than short-term. They may forget what they have done only a few hours ago, but have the clearest remembrance (记忆) of when they were very young. Psychologists tell us that we only remember few facts about our past, and that we invent the rest. It is as though we remember only the outline of a story. We then make up the details. We often do this in the way we want to remember them, usually so that we appear as the heroes of our own past or maybe victims needing sympathy (同情).1. Visual memory helps us recall a place we have been to.
单选题. Weather Map A weather map is an important tool for geographers. A succession of three of four maps presents a continuous picture of weather changes. Weather forecasts are able to determine the speed of air masses and fronts; to determine whether an individual pressure area is deepening or becoming shallow and whether a front is increasing or decreasing in intensity. They arc also able to determine whether an air mass is retaining its original characteristics or taking on those of the surface over which it is moving. Thus, a most significant function of the map is to reveal a synoptic picture of conditions in the atmosphere at a given time. All students of geography should be able to interpret a weather map accurately. Weather maps contain an enormous amount of information about weather conditions existing at the time of observation over a large geographical area. They reveal in a few minutes what otherwise would take hours to describe. The United States weather Bureau issues information about approaching storms, floods, frosts, droughts, and all climatic conditions in general. Twice a month it issues a 30-day "outlook" which is a rough guide to weather conditions likely to occur over broad areas of the United States. These 30-day outlooks are based upon an analysis of the upper air levels with often set the stage for the development of air masses, fronts, and storms. Considerable effort is being exerted today to achieve more accurate weather predictions. With the use of electronic instruments and earth satellites, enormous gains have taken place recently in identifying and tracking storms over regions which have but few meteorological stations. Extensive experiments are also in progress for weather modification studies. But the limitations of weather modification have prevented meteorological results except in the seeding of super-cooled, upslope mountainous winds which have produced additional orographical precipitation on the windward side of mountain ranges. Nevertheless, they have provided a clearer understanding of the fundamentals of weather elements.1. One characteristic of weather maps not mentioned by the author in this passage is ______.
单选题8. The old concerns lose importance and some of them vanish altogether.
单选题. Face Masks May Not Protect from Super-flu If a super-flu strikes, face masks may not protect you. Whether widespread use of masks will help, or harm, during the next worldwide flu outbreak is a question that researchers are studying furiously. No results have come from their mask research yet. However, the government says people should consider wearing them in certain situations anyway, just in case. But it's a question the public keeps asking while the government is making preparations for the next flu pandemic (大流行). So the Centers for Disease Control and Prevention (CDC) came up with preliminary guidelines. "We don't want people wearing them everywhere," said the CDC. "The overall recommendation really is to avoid exposure." When that is not possible, the guidelines say you should consider wearing a simple surgical mask if you are in one of the three following situations. First, you're healthy and can't avoid going to a crowded place. Second, you're sick and think you may have close contact with the healthy, such as a family member checking on you. Third, you live with someone who's sick and thus might be in the early stages of infection, hut still need to go out. Influenza pandemics can strike when the easy-to-mutate (变异) flu virus shifts to a strain (菌株) that people never have experienced. Scientists cannot predict when the next pandemic will arrive, although concern is rising that the Asian bird flu might trigger one if it starts spreading easily from person to person. During the flu pandemic, you should protect yourself. Avoid crowds, and avoid close contact with the sick unless you must care for someone. Why aren't masks added to this self-protection list? Because they can help trap virus-laden droplets (飞沫) flying through the air with a cough or sneeze. Simple surgical masks only filter the larger droplets. Besides, the CDC is afraid masks may create a false sense of security. Perhaps someone who should have stayed home would don (戴) an ill-fitting mask and hop on the subway instead. Nor does flu only spread through the air. Say someone covers a sneeze with his or her hand, then touches a doorknob or subway pole. If you touch that spot next and then put germy hands on your nose or mouth, you've been exposed. It's harder to rub your nose while wearing a mask, so your face may get pretty sweaty under masks. You reach under to wipe that sweat, and may transfer germs caught on the outside of the mask straight to the nose. These are the problems face masks may create for their users. Whether people should or should not use face masks still remains a question. The general public has to wait patiently for the results of the mask research scientists are still doing.1. What is the passage mainly about?
单选题. Computer Mouse The basic computer mouse is an amazingly clever invention with a relatively simple design that allows us to point at things on the computer and it is very productive. Think of all the things you can do with a mouse like selecting text for copying and pasting (涂), drawing, and even scrolling on the page with the newer mice with the wheel. Most of us use the computer mouse daily without stopping to think how it works until it gets dirty and we have to learn how to clean it. We learn to point at things before we learn to speak, so the mouse is a very natural pointing device. Other computer pointing devices include light pens, graphics (图形) tablets and touch screens, but the mouse is still our workhorse. The computer mouse was invented in 1964 by Douglas Englehart of Stanford University. As computer screens became more popular and arrow keys were used to move around a body of text, it became clear that a pointing device that allowed easier motion through the text and even selection of text would be very useful. The introduction of the mouse, with the Apple Lisa computer in 1983, really started the computer public on the road to relying on the mouse for routine (常规) computer tasks. How does the mouse work? We have to start at the bottom, so think upside down for now. It all starts with the mouse ball. As the mouse ball in the bottom of the mouse rolls over the mouse pad, it presses against and turns two shafts (轴). The shafts are connected to wheels with several small holes in them. The wheels have a pair of small electronic light-emitting devices called light-emitting diodes (LED) mounted on either side. One LED sends a light beam to the LED on the other side. As the wheels spin and a hole rotates by, the light beam gets through to the LED on the other side. But a moment later the light beam is blocked until the next hole is in place. The LED detects (发现) a changing pattern of light, converts the pattern into an electronic signal, and sends the signal (发信号) to the computer through wires in a cable that goes out the mouse body. This cable is the tail that helps give the mouse its name. The computer interprets the signal to tell it where to position the cursor on the computer screen. So far we have only discussed the basic computer mouse that most of you probably have or have used. One problem with this design is that the mouse gets dirty as the ball rolls over the surface and picks up dirt. Eventually you have to clean your mouse. The newer optical mice avoid this problem by having no moving parts.1. Most computer users want to know how the computer mouse works.
单选题7. Her novel depicts an ambitious Chinese.
单选题10. He could not tolerate the extremes of heat in the desert.
单选题9. In Britain and many other countries appraisal is now a tool of management.
单选题 Florida Hit by Cold Air Mass In January, 2003
单选题3. She stood there crying and trembling with fear.
单选题11. Their parents once lived under very severe conditions.
单选题 If headaches only occur at night
单选题14. The mountains look glorious at sunrise.
单选题13. The policemen acted quickly because lives were at stake.
单选题3. She all but fainted when she heard the news.
单选题5. The shopkeeper gave us short weight: we got 9 kilos instead of 10 kilos.
单选题 Maria Chapman