单选题The ambient noise imaging is able to locate the whales even when they are silent because ______.

单选题Don't keep us in______any longer. Tell us what happened so that we can give you a hand.

单选题 Various innovations have been introduced as ways to break off our system which forces students through a series of identical classrooms in which teachers do most of the talking and students have little opportunity to respond. Among these innovations are team teaching and teacher aides, non-graded elementary and secondary schools, independent study, curricula focused on helping students discover things for themselves rather than on trying to tell them everything, and schools designed for maximum flexibility so that students can work alone, or in small groups, or take part in large group instruction via diverse media. The aim of all these innovations is to adapt instruction more precisely to the needs of each individual student. Many people who have a strong dislike to organizing instruction scientifically and to bringing new technology into the schools and colleges fail to realize that the present system is in many respects mechanical and rigid. The vast differences in the ways students learn are disregarded when they are taught the same thing, in the same way, at the same time. There is no escaping the evidence that many students themselves feel little enthusiasm and even outright hostility for the present way schools and collages are organized and instruction is handled. Many of them resent technology, but what they object to is usually technology used as a means for handling a large number of students. Or it is programming which merely reproduces conventional classroom responds and learns, reaching new plateaus from which to climb to higher levels of understanding. Technological media can store information until it is needed or wanted. They can distribute it over distances to reach the student where he happens to be. They can present the information to the student through various senses. They can give the student the opportunity to react to the material in many ways. In short, the student's opportunities for learning can be increased and enhanced by using a wide range of instructional technology. All the available resources for instruction, including the teacher, can work together to create conditions for maximum effective learning.

单选题The pioneers of the teaching of science imagined that its introduction into education would remove the conventionality, artificiality, and backward-lookingness which were characteristic of classical studies, but they were gravely disappointed. So, too, in their time had the humanists thought that the study of the classical authors in the original would banish at once the dull pedantry and superstition of mediaeval scholasticism. The professional schoolmaster was a match for both of them, and has almost managed to make the understanding of chemical reactions as dull and as dogmatic an affair as the reading of Virgil"s Aeneid. The chief claim for the use of science in education is that it teaches a child something about the actual universe in which he is living in making him acquainted with the results of scientific discovery, and at the same time teaches him how to think logically and inductively by studying scientific method. A certain limited success has been reached in the first of these aims, but practically none at all in the second. Those privileged members of the community who have been through a secondary or public school education may be expected to know something about the elementary physics and chemistry of a hundred years ago, but they probably know hardly more than any bright boy can pick up from an interest in wireless or scientific hobbies out of school hours. As to the learning of scientific method, the whole thing is probably a farce. Actually, for the convenience of teachers and the requirements of the examination system, it is necessary that the pupils not only do not learn scientific method but learn precisely the reverse, that is, to believe exactly what they are told and to reproduce it when asked, whether it seems nonsense to them or not. The way in which educated people respond to such quackeries as spiritualism or astrology, not to say more dangerous ones such as racial theories or currency myths, shows that fifty years of education in the method of science in Britain or Germany has produced no visible effect whatever. The only way of learning the method of science is the long and bitter way of personal experience, and, until the educational or social systems are altered to make this possible, the best we can expect is the production of a minority of people who are able to acquire some of the techniques of science and a still smaller minority who are able to use and develop them.

单选题When he applied for a ______ in the office of the local newspaper he was told to see the manager. A. location B. profession C. career D. position

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单选题The prime minister's proposal for new taxes created such a(n)______that his government fell.

单选题Every community requires a wholesome, dependable supply of water, and every community generates liquid and solid wastes. A. considerable B. healthful C. immediate D. secure

单选题Humanity uses a little less than half the water available worldwide. Yet occurrences of shortages and droughts are causing famine and distress in some areas, and industrial and agricultural by-products are polluting water supplies. Since the world's population is expected to double in the next 50 years, many experts think we are on the edge of a widespread water crisis. But that doesn't have to be the outcome. Water shortages do not have to trouble the world—if we start valuing water more than we have in the past. Just as we began to appreciate petroleum more after the 1970s oil crises, today we must start looking at water from a fresh economic perspective. We can no longer afford to consider water a virtually free resource of which we can use as much as we like in any way we want. Instead, for all used except the domestic demand of the poor, governments should price water to reflect its actual value. This means charging a fee for the water itself as well as for the supply costs. Governments should also protect this resource by providing water in more economically and environmentally sound ways. For example, often the cheapest way to provide irrigation water in the dry tropics is through small-scale projects, such as gathering rainfall in depressions and pumping it to nearby cropland. No matter what steps governments take to provide water more efficiently, they must change their institutional and legal approaches to water use. Rather than spread control among hundreds or even thousands of local, regional, and national agencies that watch various aspects of water use, countries should set up central authorities to coordinate water policy.

单选题{{B}}Text 1{{/B}} The food you eat does more than provide energy. It can have a dramatic effect on your body's ability to fight off heart disease, cancer, diabetes, high blood pressure, stroke, and weak bones. With remarkable consistency, recent research has found that a diet high in plant-based foods—fruits, vegetables, dried peas and beans, grains, and starchy staples such as potatoes—is the body's best weapon in thwarting many health-related problems. These foods work against so many diseases that the same healthy ingredients you might use to protect your heart or ward off cancer will also benefit your intestinal tract and bones. Scientists have recently estimated that approximately 30 to 40 percent of all cancers could be avoided if people ate more fruits, vegetables, and plant-based foods and minimized high-fat, high-calorie edibles that have scant nutritional value. Up to 70 percent of cancers might be eliminated if people also stopped smoking, exercised regularly, and controlled their weight. In the past, researchers had linked fat consumption with the development of cancers, but they currently believe that eating fruits, vegetables, and grains may be more important in. preventing the disease than not eating fat. "The evidence about a high-fat diet and cancer seemed a lot stronger several years ago than it does now," says Melanie Polk, a registered dietitian and director of nutrition education at the American Institute for Cancer Research. The road to strong bones is paved with calcium-rich food. Leafy green vegetables and low-fat dairy products are excellent sources of calcium, the mineral that puts stiffness into your skeletal system and keeps your bones from turning rubbery and fragile. Your body uses calcium for mom than keeping your bones strong. Calcium permits cells to divide, regulates muscle contraction and relaxation, and plays an important role in the movement of protein and nutrients inside cells. If you don't absorb enough from what you eat to satisfy these requirements, your body will take it from your bones. Because your body doesn't produce this essential mineral, you must continually replenish the supply. Even though the recommended daily amount is 1,200 mg, most adults don't eat more than 500 mg. One mason may have been the perception that calcium-rich dairy products were also loaded with calories. "In the past, women, in particular, worded that dairy products were high in calories, "says Letha Y. Griffin, M. D., of Peachtree Orthopaedics in Atlanta." But today you can get calcium without eating any high-fat or high-calorie foods by choosing skim milk or low-fat yogurt. "Also, low-fat dairy products contain phosphorous and magnesium and are generally fortified with vitamin D, all of which help your body absorb and use calcium. If you find it difficult to include enough calcium in your diet, ask your doctor about supplements. They are a potent way to get calcium as well as vitamin D and other minerals. But if you rely on pills instead of a calcium-rich diet, you won't benefit from the other nutrients that food provides. Getting the recommended vitamin D may be easy, since your body makes the vitamin when your skin is exposed to the sun's rays.

单选题She makes no ______of their affair in public and he understands that he is not to refer to it with these new acquaintances. A. concealment B. compliment C. amendment D. acknowledgement

单选题Human facial expressions differ from those of animals in the degree to which they can be ______ controlled and modified.

单选题In the popular Western imagination, India continues to be a country in backwardness and poverty with little to show______scientific innovation or technological achievement.

单选题We know the couple were Ureluctant/U to have their daughter marry him.

单选题I am grateful for your ______ invitation, and I'd like to accept your offer with pleasure.(2005年中国科学院考博试题)

单选题According to the passage glass cools and becomes rigid differently from metals because ______.

单选题The______action of the policemen saved the people in the house from being burnt. (厦门大学2011年试题)