题目内容
When an invention is made, the inventor has three possible 【C1】______ of action open to him: he can give the invention to file world by publishing it, keep the idea 【C2】______ , or patent it.
A 【C3】______ patent is the result of a bargain 【C4】______ between an inventor and the state, but the inventor gets a limited period of monopoly and publishes full details of his invention to the public after that period 【C5】______ .
Only in the most exceptional circumstances 【C6】______ the lifespan of a patent 【C7】______ to alter this normal process of events
The longest extension ever 【C8】______ was to Georges Valensi; his 1939 patent for color TV receiver circuit was extended until 1971 because for most of the patent's normal life there was no color TV to 【C9】______ and thus no hope for reward for the invention.
Because a patent remains permanently 【C10】______ after it has terminated, the shelves of the library attached to the 【C11】______ office contain details of literally millions of ideas that are free for anyone to use and, if 【C12】______ than half a century, sometimes even re-patent. Indeed, patent experts often advise anyone 【C13】______ to avoid the high cost of conducting a search through【C14】______ patents that the one sure way of violation of any other inventor's right is to plagiarize a dead patent. Likewise, because publication of an idea in any other form【C15】______ invalidates further patents on that idea, it is traditionally 【C16】______ to take ideas from other areas of print. Much modem technological advance is【C17】______ on these presumptions of legal security.
Anyone closely 【C18】______ in patents and inventions soon learns that most "new" ideas are, in fact, as old as the hills. It is theft reduction to commercial practice, either through necessity or dedication, or through the availability of new technology,【C19】______ makes news and money. The basic patent for the theory for magnetic recording dates back to 1886. Many of the original ideas behind television originate 【C20】______ the late 19th and early 20th century. Even the Volkswagen rear engine car was anticipated by a 1904 patent for a cart with the horse at the rear.
【C1】______
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Without water no living thing can survive, and one feature of the true desert landscape is the absence of vegetation. With little rain and hardly any vegetation the land suffers under the sun. There are virtually no clouds or trees to protect the earth's surface and it can be burning hot. Under the sun, soils break up and crack. Wind and torrential rain sweep away and erode the surface further. Eight million square kilometers of the world's land surface is desert. Throughout history deserts have been expanding and retreating again. Cave paintings show that parts of the Sahara Desert were green and fertile about 10,000 years ago, and even animals like elephants and giraffes roamed the land. Fossil and dunes found in fertile and damp parts of the world show that these areas were once deserts. But now the creation of new desert areas is happening on a colossal scale. Twenty million square kilometers, an area twice the size of Canada, is at a high to very high risk of becoming desert. With a further 1.25 million square kilometers under moderate risk, an area covering 30% of the earth's land surface is desert, becoming desert, or in danger of becoming desert. The rate of growth of deserts is alarming. The world's drylands which are under threat include some of the most important stock-rearing and wheat-growing areas and are the homes of 600--700 million people. These regions are becoming deserts at the rate of more than 58, 000 square kilometers a year or 44 hectares a minute. In North Africa at least 100,000 hectares of cropland am lost each year. At this rate there is a high risk that we will be confined to living on only 50% of this planet's land surface within one more century unless we am able to do something about it.
What does the passage tell us about rainfall in the desert？
There is no question that the old style. of air pollution could kill people. In one week following the infamous "peasouper" fog in December 1952, 4,700 people died in London. Most of these people were elderly and already had heart or lung diseases. A series of these killer fogs eventually led to the British Passing the Clean Air Act which restricted the burning of coal.
Fortunately the effect of smog on the lungs is not so dramatic. Scientists have now conducted a number of laboratory experiments in which volunteers are exposed to ozone inside a steel chamber for a few hours. Even at quite low concentrations there is a reversible fall in lung function, an increase in the irritability of the lungs and evidence of airway inflammation (发炎) . Although irritable and inflamed lungs are particularly seen in people with asthma (哮喘) and other lung diseases, these effects of ozone also occur in healthy subjects. Similar changes are also seen after exposure to nitrogen dioxide, although there is some disagreement about the concentration at which they occur.
Other studies have found that people living in areas with high levels of pollution have more symptoms and worse lung function than those living in areas with clean air. Groups of children attending school camps show falls in lung function even at quite low concentrations of ozone. There is also a relationship between ozone levels and hospital admissions for asthma, both in North America and Australia. It is suspected that long-term exposure to smog may result in chronic bronchitis (支气管炎) and emphysema (肺气肿), but this has yet to be proven.
Recently an association has been found between the levels of particles in the air and death rates in North American cities. The reason for this association is not understood and as vet there is no evidence this occurs in Australia. However, we do know that hazy days are associated with more asthma attacks in children.
Which of the following is NOT the result of laboratory experiments？
所有经典都有其局限性，不加选择地将经典灌输给学生确实是缺乏教育责任的表现。但将经典进行删节，然后将_______的“洁本”教给学生，就一定能给学生营造出理想的“世外桃源”吗？填人划横线部分最恰当的一项是（）。
在下列程序代码中，主程序调用add(x)时，若参数传递采用引用方式，则其输出结果为(34)，若参数传递采用传值方式，则输出结果为(35)。
(61)
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