2020年12月英语四级答案-2020年12月英语四级晨读美文

【#四六级考试# 导语】不做“说话的巨人，行动的矮子”。说再多的漂亮话，也不如做一件实实在在的漂亮事，行动永远是迈向成功的第一步，想永远只会在原地踏步。对于考试而言亦是如此，每天进步一点点，基础扎实一点点，通过考试就会更容易一点点。以下为“2020年12月英语四级晨读美文”，欢迎阅读参考！更多相关讯息请关注©文档大全网！

【篇一】2020年12月英语四级晨读美文

　　In so many ways, cyberspace 1 mirrors the real world. People ask for information, play games, and share hobby tips. Others buy and sell products. Still others look for friendship, or even love.

　　Unlike the real world, however, your knowledge about a person is limited to words on a computer screen. Identity and appearance mean very little in cyberspace. Rather, a person's thoughts-or at least the thoughts they type — are what really count. So even the shyest person can become a chat-room star2.

　　Usually, this "faceless"communication doesn't create problems. Identity doesn't really matter when you're in a chat room discussing politics or hobbies. In fact, this emphasis on the ideas themselves makes the Internet a great place for exciting conversation. Where else can so many people come together to chat?

　　But some Internet users want more than just someone to chat with. They're looking for serious love relationships. Is cyberspace a good place to find love? That answer depends on whom you ask. Some of these relationships actually succeed. Others fail miserably.

　　Supporters of online relationships claim that the Internet allows couples to get to know each other intellectually3 first. Personal appearance doesn't get in the way4. But critics of online relationships argue that no one can truly know another person in cyberspace. Why? Because the Internet gives users a lot of control over how others view them. Internet users can carefully craft their words to fit whatever image they want to give. And they don't have to worry about what their " nonverbal"communication is doing for their image. In a sense, they're not really themselves.

　　All of this may be fine if the relationship stays in cyberspace. But not knowing a person is a big problem in a love relationship. With so many unknowns, it's easy to let one's imagination " fill in the blanks."This inevitably leads to disappointment when couples meet in person. How someone imagines an online friend is often quite different than the real person.

　　So, before looking for love in cyberspace, remember the advice of Internet pioneer Clifford Stoll: "Life in the real world is far richer than anything you'll find on a computer screen."

【篇二】2020年12月英语四级晨读美文

　　Can electricity cause cancer? In a society that literally runs on electric power, the very idea seems preposterous. But for more than a decade, a growing band of scientists and journalists has pointed to studies that seem to link exposure to electromagnetic fields with increased risk of leukemia and other malignancies. The implications are unsettling, to say the least, since everyone comes into contact with such fields, which are generated by everything electrical, from power lines and antennas to personal computers and micro-wave ovens. Because evidence on the subject is inconclusive and often contradictory, it has been hard to decide whether concern about the health effects of electricity is legitimate—or the worst kind of paranoia.

　　Now the alarmists have gained some qualified support from the U.S. Environmental Protection Agency. In the executive summary of a new scientific review, released in draft form late last week, the EPA has put forward what amounts to the most serious government warning to date. The agency tentatively concludes that scientific evidence"suggests a casual link" between extremely low-frequency electromagnetic fields—those having very longwave-lengths—and leukemia, lymphoma and brain cancer, While the report falls short of classifying ELF fields as probable carcinogens, it does identify the common 60-hertz magnetic field as "a possible, but not proven, cause of cancer in humans."

　　The report is no reason to panic—or even to lost sleep. If there is a cancer risk, it is a small one. The evidence is still so controversial that the draft stirred a great deal of debate within the Bush Administration, and the EPA released it over strong objections from the Pentagon and the White House. But now no one can deny that the issue must be taken seriously and that much more research is needed.

　　At the heart of the debate is a simple and well-understood physical phenomenon: When an electric current passes through a wire, tit generates an electromagnetic field that exerts forces on surrounding objects, For many years, scientists dismissed any suggestion that such forces might be harmful, primarily because they are so extraordinarily weak. The ELF magnetic field generated by a video terminal measures only a few milligauss, or about one-hundredth the strength of the earth's own magnetic field, The electric fields surrounding a power line can be as high as 10 kilovolts per meter, but the corresponding field induced in human cells will be only about 1 millivolt per meter. This is far less than the electric fields that the cells themselves generate.

　　How could such minuscule forces pose a health danger? The consensus used to be that they could not, and for decades scientists concentrated on more powerful kinds of radiation, like X-rays, that pack sufficient wallop to knock electrons out of the molecules that make up the human body. Such "ionizing" radiations have been clearly linked to increased cancer risks and there are regulations to control emissions.

　　But epidemiological studies, which find statistical associations between sets of data, do not prove cause and effect. Though there is a body of laboratory work showing that exposure to ELF fields can have biological effects on animal tissues, a mechanism by which those effects could lead to cancerous growths has never been found.

　　The Pentagon is for from persuaded. In a blistering 33-page critique of the EPA report, Air Force scientists charge its authors with having "biased the entire document" toward proving a link. "Our reviewers are convinced that there is no suggestion that (electromagnetic fields) present in the environment induce or promote cancer," the Air Force concludes. " It is astonishing that the EPA would lend its imprimatur on this report." Then Pentagon's concern is understandable. There is hardly a unit of the modern military that does not depend on the heavy use of some kind of electronic equipment, from huge ground-based radar towers to the defense systems built into every warship and plane.

【篇三】2020年12月英语四级晨读美文

　　Our planet is thirsty — thirsty because it is hungry. It takes one thousand times more water to feed the human population than it does to satisfy its thirst.

　　Water lies at the core of sustainable development concerns, and its rational and equitable management is crucial for human survival. That was one of the key messages to arise from the World Summit on Sustainable Development2 that was held in Johannesburg this summer. Next year's Third World Water Forum in Japan will address this issue in greater depth.

　　It is therefore fitting that this year's World Food Day spotlights the role of water in food security. Without water, there can be no food production. In fact, the agricultural sector is the user of 70 percent of the planet's water supply. In a world in which per capita water availability is declining, we need to focus on appropriate water management if we are to sufficiently increase food production, with a view to reduce hunger and malnutrition, and feed a population expected to rise to 8 billion in 30 years'time.

　　Shortage of water threatens extensive agricultural regions in developing countries and fans the prospect of food crises. At present, twenty countries do not have enough water to produce the food their populations need. In some cases, the overexploitation of water resources undermines future agricultural production, while in others, their underexploitation inhibits development.

　　The combined vicious impact of poverty, rising demand for food and insufficient availability of water therefore poses a serious challenge for world food security and universal access to clean water. One billion people are deprived of clean water, and most of these people are also hungry. They live in rural areas and agriculture is their main source of income.

　　How are we to ensure water availability and food security, while safeguarding the environment? At present, more than one-third of the world's food production comes from the irrigated areas that make up 16 percent of the planet's arable land. Irrigated farming is at least twice as productive as rainfed farming3, and during the next 30 years some 70 percent of additional food production in developing countries should come from irrigated land.

　　It is urgent to avoid poor irrigation practices that have often led to diminishing water supplies, land degradation and spread of disease . Far too often, more water is being pumped than can possibly be recharged. Also , too much water is being lost along canals, because of leakage , wastage , seepage or evaporation. Too many schemes are losing productivity because of inappropriate drainage, waterlogging and a build-up of salts in the soil.

　　We thus have to turn increasingly to adopt integrated watershed management, curb the upstream deforestation that generates flooding and erosion, and significantly increase investment in water control infrastructure. Finally, water use will be sustainable only if it is done in a socially equitable manner.

　　New water policy, and institutions and laws will facilitate the integrated management of river basins and water resources by all stakeholders, in a climate of transparency, accountability and social justice.

　　The cooperation of all development partners, the public, private and non-profit sectors at national and international level, will be indispensable to resolve conflicts of interest, mobilize substantial financial resources and create conditions for a fairer distribution of food and water.

　　The countries of Africa , the Middle East and southern Asia that are already facing serious water shortages will see their situation rapidly worsen unless there is stronger solidarity between the regions of abundance and the regions of scarcity. Such solidarity is necessary if we are to avoid a proliferation and aggravation of tensions relating to water .

2020年12月英语四级晨读美文.doc

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