2022年职称英语考试《理工类》考试共65题，分为单选题和多选题和判断题和计算题和简答题和不定项。小编为您整理历年真题5道练习题，附答案解析，供您备考练习。

1、WaterThe second most important constituent (构成成份) of the biosphere (生物圈) is liquid water. This can only exist in a very narrow range of temperatures, since water freezes at 0℃ ａｎｄ　boils at 100℃. Life as we know it would only be possible on the surface of a planet which had temperatures somewhere within this narrow range.The earth\'s supply of water probably remains fairly constant in quantity. The total quantity of water is not known very accurately, but it is about enough to cover the surface of the globe to a depth of about two ａｎｄ　three - quarter kilometers. Most of it is in the form of the salt water of the oceans about 97 percent. The rest is fresh, but three -quarters of this is in the form of ice at the Poles ａｎｄ　on mountains, ａｎｄ　cannot be used by living systems until melted. Of the remaining fraction, which is somewhat less than one percent of the whole, there is 10 -20 times as much stored underground water as there is actually on the surface. There is also a tiny, but extremely important fraction of the water supply which is present as water vapour in the atmosphere.Water vapour in the atmosphere is the channel through which the whole water circulation (循环) of the biosphere has to pass. Water evaporated (蒸发) from the surface of the oceans, from lakes ａｎｄ　rivers ａｎｄ　from moist (潮湿的) earth is added to it. From it the water comes out again as rain ｏｒsnow, falling on either the sea ｏｒthe land. There is, as might be expected, a more intensive evaporation per unit area over the sea ａｎｄ　oceans than over the land, but there is more rainfall over the lａｎｄ　than over the oceans ａｎｄ　the balance is restored by the runoff from the lａｎｄ　in the form of rivers.The word "fraction" in the second paragraph means ______.【单选题】

A.a very small amount

B.a large area

C.an important system

D.a majｏｒsource of information

正确答案:A

答案解析:本题难度不大，文章第二段第四句谈到剩余部分大约小于1%，可以判断fraction意思是指“很少一部分”，此外也可迅速查词典，确定答案，答案是A。

2、Arctic MeltEarth\'s North ａｎｄ　South Poles are famous fｏｒbeing cold ａｎｄ　icy. Last year, however, the amount of ice in the Arctic Ocean (北冰群) fell to a record low.Normally, ice builds in Arctic waters around the North Pole each winter ａｎｄ　shrinks(缩小) during the summer. But fｏｒmany years, the amount of ice left by the end of summer has been declining.Since 1979, each decade has seen an 11.4 percent ｄｒｅｐin end of summer ice cover. Between 1981 ａｎｄ　2000, ice in the Arctic lost 22 percent of its thickness, becoming 1.13 meters thinner.Last summer, Arctic sea ice reached its thinnest levels. By the end of summer 2007, the ice had shrunk to cover just 4.2 million square kilometers. That\'s 38 percent less area than the average cover at that time of year. ａｎｄ　it\'s a very large 23 percent below the previous record low, which was ｓｅｔjust 2 years ago. This continuing trend has made scientists concerned to.There may be several reasons fｏｒthe ice melt, says Jinlun Zhang, an oceanographer (海洋学家)at the University of Washington in Seattle. Unusually strong winds blew through the Arctic last summer. The winds pushed much of the ice out of the central Arctic, leaving a large area of thin ice ａｎｄ　open water.Scientists also suspect that fewer clouds cover the Arctic now than in the past. Clearer skies allow more sunlight to reach the ocean. The extra heat warms both the water ａｎｄ　the atmosphere. In parts of the Arctic Ocean last year, surface temperatures were 3.57 Celsius warmer than the average ａｎｄ　1.5c warmer than the previous record.With both air ａｎｄ　water getting warmer, the ice is melting from both above ａｎｄ　below. In some parts of the Beaufort Sea, north of Alaska ａｎｄ　western Canada, ice that measured 3.3 meters thick at the beginning of the summer was measured just 50 cm by season\'s endThe new measurements suggest that melting is far more severe than the thinking of scientists. Some scientists fear that the Arctic is stuck in a warming trend.It can be learned from the last sentence that ______.【单选题】

A.the ice melt in the Arctic may never stop

B.scientists are trying hard to stop the ice melt in the Arctic

C.scientists are delighted to find out what is going on in the Arctic

D.the warming trend in the Arctic can be reversed in the near future

正确答案:A

答案解析:本题难度不大，最后一句话的句意不难理解。文章最后一句谈到，科学家们担心北极处于变暖趋势，而且不能挽回，答案是B。

3、One Good Reason to Let Smallpox LiveIt\'s now a fair bet that we will never see the total extinction (灭绝) of the smallpox (天花) virus. When smallpox was completely got rid of in the world, scientists wanted to destroy the killer virus in the last two labs, one in the US ａｎｄ　one in Russia. They asked: If smallpox has truly gone from the planet, what point was there in keeping these reserves?In reality, of course, it was naive to imagine that everyone would let go of such a powerful potential weapon. Undoubtedly several nations still have a few vials (小药瓶). ａｎｄ　the last "official" stocks of live Virus bred mistrust of the US ａｎｄ　Russia, fｏｒno obvious gain.Now American researchers have _____ an animal model of the human disease, opening the way fｏｒtests on new treatments ａｎｄ　vaccines(疫苗). So once again there\'s a good reason to the virus, just in keep the disease puts in a reappearance.How do we case with the mistrust of the US ａｎｄ　Russia? deal. Keep the virus Simple international support in a well - guarded UN laboratory that\'s open to all countries. The US will object, of course, just as it with a multilateral (多边的) approach to just about everything. But it doesn\'t mean the idea is rejects. If the virus is useful, then let\'s wrong it the servant of all humanity make not just a part of it.【单选题】

A.missed

B.held

C.found

D.checked

正确答案:C

答案解析:本题有一定难度，依据上下文逻辑，文章此处要用“发现”的意思，答案是C。

4、One Good Reason to Let Smallpox LiveIt\'s now a fair bet that we will never see the total extinction (灭绝) of the smallpox (天花) virus. When smallpox was completely got rid of in the world, scientists wanted to destroy the killer virus in the last two labs, one in the US ａｎｄ　one in Russia. They asked: If smallpox has truly gone from the planet, what point was there in keeping these reserves?In reality, of course, it was naive to imagine that everyone would let go of such a powerful potential weapon. Undoubtedly several nations still have a few vials (小药瓶). ａｎｄ　the last "official" stocks of live Virus bred mistrust of the US ａｎｄ　Russia, fｏｒno obvious gain.Now American researchers have found an animal model of the human disease, opening the way fｏｒtests on new treatments ａｎｄ　vaccines(疫苗). So once again there\'s a good reason to the virus, just in _____ the disease puts in a reappearance.How do we case with the mistrust of the US ａｎｄ　Russia? deal. Keep the virus Simple international support in a well - guarded UN laboratory that\'s open to all countries. The US will object, of course, just as it with a multilateral (多边的) approach to just about everything. But it doesn\'t mean the idea is rejects. If the virus is useful, then let\'s wrong it the servant of all humanity make not just a part of it.【单选题】

A.put

B.keep

C.remove

D.study

正确答案:B

答案解析:本题难度不大，依据上下文逻辑，文章此处要用“保存”的意思，答案是B。

5、Radiocarbon DatingNowadays scientists can answer many questions about the past through a technique called radiocarbon (放射性碳), ｏｒcarbon - 14 dating. One key to understanding how ａｎｄ　why something happened is to discover when it happened.Radiocarbon dating was developed in the late 1940s by physicist Willard F. Libby at the University of Chicago. An atom of ordinary carbon, called carbon -12, has six protons (质子) ａｎｄ　six neutrons (中子) in its nucleus (原子核). Carbon - 14, ｏｒC - 14, is a radioactive, unstable form of carbon that has two extra neutrons. It returns to a more stable form of carbon through a process called decay (衰减). This process involves the loss of the extra neutrons ａｎｄ　energy from the nucleus.In Libby\'s radiocarbon dating technique, the weak radioactive emissions(放射)from this decay process are counted by instruments such as a radiation detectｏｒａｎｄ　counter. The decay rate is used to determine the proportion of C -14 atoms in the sample being dated.Carbon - 14 is produced in the Earth\'s atmosphere when nitrogen(氮) - 14, ｏｒN - 14, interacts with cosmic rays (宇宙射线). Scientists believe since the Earth was formed, the amount of nitrogen in the atmosphere has remained constant. Consequently, C -14 formation is thought to occur at a constant rate. Now the ratio of C -14 to other carbon atoms in the atmosphere is known. Most scientists agree that this ratio is useful fｏｒdating items back to at least 50,000 years.All life on Earth is made of organic molecules (分子) that contain carbon atoms coming from the atmosphere. So all living things have about the same ratio of C -14 atoms to other carbon atoms in their tissues (组织). Once an organism (有机体) dies it stops taking in carbon in any form, ａｎｄ　the C -14 already present begins to decay. Over time the amount of C - 14 in the material decreases ａｎｄ　the ratio of C - 14 to other carbon atoms goes down. In terms of radiocarbon dating, the fewer C -14 atoms in a sample, the older that sample is.The half - life of C - 14 is about 25 ,000 years.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:C

答案解析:本题有较大难度，答案依据不明显，需要通读全文作出判断。通读全文后可以发现文章并未提及碳的半衰期是25，000年，所以本题是未提及的，答案是C。