泽熙美文材料题
根据以下材料，回答45-49题
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 long wave-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 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, it 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 far 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.
45 [单选题] The main idea of this passage is_______. 查看材料
A.studies on the cause of cancer
B.controversial viewpoints in the cause of cancer
C. the relationship between electricity and cancer
D.different ideas about the effect of electricity on cancer
正确答案：D
参考解析：主旨题。全文主要围绕人们关于电流对癌症影响的不同观点展开叙述，分别介绍了科学家、美国环保署、美国国防部等的观点。故本题选D。
46 [单选题] The view point of the EPA is_______. 查看材料
A.there is casual link between electricity and cancer
B.electricity really affects cancer
C. controversial
D. low frequency electromagnetic field is a possible cause of cancer
正确答案：A
参考解析：细节题。根据关键词定位至原文第二段。根据“The agency tentatively concludes that scientific evidence‘suggests a casual link’between extremely low-frequency electromagnetic fields–those having very long wave．lengths—and leukemia，lymphoma and brain cancer…”可知，美国环保署认为电流与癌症之间有着某种难以确定的关系。故本题选A。
47 [单选题] Why did the Pentagon and White House object to the release of the report? 查看材料
A.It may stir a great deal of debate among the Administration.
B. Every unit of the modern military has depended on the heavy use of some kind of electronic equipment.
C. The Pentagon’s concern was understandable.
D. They had different arguments.
正确答案：B
参考解析：细节题。原文最后一段指出现代军事部门几乎没有不依赖大量电子设备的。这就是美国国防部和政府反对该国环保署公布报告的理由。根据第三段可知，证据的不确定性引起了政府内部的讨论，A项“报告会在政府内引起激烈的讨论”不是美国国防部和政府反对公布报告的理由，而是报告引起的结果。C、D两项均不是美国国防部和该国政府反对公布报告的理由。故本题选B。
48 [单选题] It can be inferred from the physical phenomenon that_______. 查看材料
A.the force of the electromagnetic field is too weak to be harmful
B. the force of the electromagnetic field is weaker than the electric field that the cells generate
C.electromagnetic field may affect health
D. only more powerful radiation can knock electron out of human body
正确答案：C
参考解析：推断题。根据文章第四段可知这一物理现象是电流通过时会产生电磁场，电磁场会对周围环境造成影响。接着该段及接下来的内容指出电磁场很微弱，因此科学家们不认为其会危害健康，因而之前也没有针对电磁场对健康的影响的研究(科学家们更关注其他辐射性更强的物体对健康的危害，如X光)。因此A项“电磁场过于微弱不足以产生危害”过于武断。B项文章有明确提及，不属于推断出的内容。D项表述过于绝对，无法从文章推断出。倒数第二段提到“exposure to ELF fields can have biological effects on animal tissues”，由此可推选出C项“电磁场也许会影响健康”。故本题选C。
49 [单选题] What do you think ordinary citizens may do after reading the different arguments? 查看材料
A.They are indifferent.
B. They are worried very much.
C. They may exercise prudent avoidance.
D. They are shocked.
正确答案：C
参考解析：推断题。全文主要围绕着人们关于电流对癌症影响的不同的观点展开叙述。因为电流是否对健康有影响这一问题仍然有争议，所以人们更可能采取谨慎的回避措施。故本题选C。
材料题
根据以下材料，回答50-54题
The mythology of a culture can provide some vital insights into the beliefs and values of that culture. By using fantastic and sometimes incredible stories to create an oral tradition by which to explain the wonders of the natural world and teach lessons to younger generations, a society exposes those ideas and concepts held most important. Just as important as the final lesson to be gathered from the stories, however, are the characters and the
