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生态系统都是不同程度的( )系统，不断的从外界输入能量和物质，经过转换以后变为输出，从而维持系统的有序状态。
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Why the inductive and mathematical sciences, ,after their first rapid development at the culmination of Greek civilization, advanced so slowly for two thousand years and why in the following two hundred years a knowledge of natural and mathematical science has accumulated, which so vastly exceeds all that was previously known that these sciences may be justly regarded as the products of our own times are questions which have interested the modern philosopher not less than the objects with which these sciences are more immediately conversant. Was it the employment of a new method of research, or in the exercise of greater virtue in the use of the old methods, that this singular modern phenomenon had its origin Was the long period one of arrested development, and is the modern era one of normal growth Or should we ascribe the characteristics of both periods to sc-called historical accidents to the influence of conjunctions in circumstances of which no explanation is possible, save in the omnipotence and wisdom of a guiding ProvidenceThe explanation which has become commonplace, that the ancients employed deduction chiefly in their scientific inquiries, while the moderns employ induction, proves to be too narrow, and fails upon close examination to point with sufficient distinctness the contrast that is evident between ancient and modern scientific doctrines and inquiries. For all knowledge is founded on observation, and proceeds from this by analysis, by synthesis and analysis, by induction and deduction, and if possible by verification, or by new appeals to observation under the guidance of deduction--by steps which are indeed correlative parts of one method; and the ancient sciences afford examples of every one of these methods, or parts of one method, which have been generalized from the examples of science.A failure to employ or to employ adequately any one of these partial methods, an imperfection in the arts and resources of observation and experiment, carelessness in observation, neglect of relevant facts, by appeal to experiment and observation--these are the faults which cause all failures to ascertain truth, whether among the ancients or the moderns; but this statement does not explain why the modern is possessed of a greater virtue, and by what means he attained his superiority. Much less does it explain the sudden growth of science in recent time.The attempt to discover the explanation of this phenomenon in the antithesis of "facts" and "theories" or "facts" and "ideas"--in the neglect among the ancients of the former, and their too exclusive attention to the latter proves also to be too narrow, as well as open to the charge of vagueness. For in the first place, the antithesis is not complete. Facts and theories are not coordinate species. Theories, if true, are facts a particular class of facts indeed, generally complex, and if a logical connection subsists between their constituents, have all the positive attributes of theories.Nevertheless, this distinction, however inadequate it may be to explain the source of true method in science, is well founded, and connotes an important character in true method. A fact is a proposition of simple. A theory, on the other hand, if true has all the characteristics of a fact, except that its verification is possible only by indirect, remote, and difficult means. To convert theories into facts is to add simple verification, and the theory thus acquires the full characteristics of a fact. The title that best expresses the ideas of this passage is （）
From the health point of view we are living in a marvelous age. We are immunized from birth against many of the most dangerous diseases. A large number of once fatal illnesses can now be cured by modern drugs and surgery. It is almost certain that one day remedies will be found for the most stubborn remaining diseases. The expectation of life has increased enormously. But though the possibility of living a long and happy life is greater than ever before, every day we witness the incredible slaughter of men, women and children on the roads. Man versus the motor-car ! It is a never-ending battle which man is losing. Thousands of people the world over are killed or horribly killed each year and we are quietly sitting back and letting it happen.It has been rightly said that when a man is sitting behind a steering wheel, his car becomes the extension of his personality. There is no doubt that the motor-car often brings out a man’s very worst qualities. People who are normally quiet and pleasant may become unrecognizable when they are behind a steering-wheel. They swear, they are ill-mannered and aggressive, willful as two-year-old and utterly selfish. All their hidden frustrations, disappointments and jealousies seem to be brought to the surface by the act of driving.The surprising thing is that society smiles so benignly on the motorist and seems to condone his behaviour. Everything is done for his convenience. Cities are allowed to become almost uninhabitable because of heavy tragic; towns are made ugly by huge car parks; the countryside is desecrated by road networks; and the mass annual slaughter becomes nothing more than a statistic, to be conveniently forgotten.It is high time a world code were created to rcduce this senseless waste of human life. With regard to driving, the laws of some countries are notoriously lax and even the strictest are not strict enough. A code which was universally accepted could only have a dramatically beneficial effect on the accident rate. Here are a few examples of some the things that might be done. The driving test should be standardized and made far more difficult than it is; all the drivers should be made to take a test every three years or so; the age at which young people are allowed to drive any vehicle should be raised to at least 21; all vehicles should be put through stringent annual tests for safety. Even the smallest amount of alcohol in the blood can impair a person’s driving ability. Present drinking and driving laws (where they exist) should be mad much stricter. Maximum and minimum speed limits should be imposed on all roads. Governments should lay down safety specifications for manufacturers, as has been done in the USA. All advertising stressing power and performance should be banned. These measures may sound inordinately harsh. But surely nothing should be considered as to severe if tit results in reducing the annual toll of human life. After all, the world is for human beings, not motor-cars. What does the author think of society toward motorists（）
（）computer is more essential to a modern business than （）typewriter.
Doctors' efforts to develop a new way to see the brain working have so far （）with satisfaction.
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