2023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。小编每天为您准备了5道每日一练题目（附答案解析），一步一步陪你备考，每一次练习的成功，都会淋漓尽致的反映在分数上。一起加油前行。

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、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。

3、Cell Phones1. Believe it ｏｒnot, cell phones have been around fｏｒover a quarter of a century. The first commercial cell phone system was developed by the Japanese in 1979, but cell phones have changed a lot since that time. The early cell phones were big ａｎｄ　heavy but they have developed into small ａｎｄ　light palm sized models. There are huge developments in their functions, too. We have had call forwarding, text messaging, answering services ａｎｄ　hands - free use fｏｒyears, but now there are new facilities, such as instant access to the Internet ａｎｄ　receiving ａｎｄ　sending photos.2. Cell phones have become very common in our lives. Recent statistics suggest one in three people on the planet now have cell phone, ａｎｄ　most of them say they couldn\'t live without one, Cell phones are used in every area of our lives ａｎｄ　have become a necessary tool, used fｏｒessential arrangements, social contact ａｎｄ　business. It easier to call fｏｒhelp on the highway. It possible to keep in touch with people "on the move" when people are traveling.3. Cell phones have made communication easier ａｎｄ　have reduced the need fｏｒfamily arguments f We can use cell phones to let our family know we\'ll be late ｏｒif there\'s a sudden change of plan ｏｒan emergency. Cell phones have eased the worries of millions of parents when their teenagers are out late. They can now contact their children at any time.4. This does not mean that cell phones are all good news. Cell phones have brought with them a number of new headaches fｏｒtheir owners. It costs a lot to replace stolen phones, It is becoming a frequent occurrence, ａｎｄ　have you ever seen such a huge phone bills? More serious, however, Cell phones bring the potential health problem. There are fears that radiation from the phones may cause brain tumｏｒ肿瘤). This may be a time bomb waiting to happen to younger people who have grown up with cell phones. They simply can\'t live without cell phones!Paragraph 2 ______【单选题】

A.Cell phones ａｎｄ　the family

B.Commercial cell phone systems

C.Cell phones in everyday life

D.Cell phones fｏｒteenagers

E.History of cell phones

F.Problems with cell phones

正确答案:E

答案解析:本题有一定的难度，需要有一定的归纳概括能力。可以发现，文章第一段主要手机的发展历史做了简单论述，E项History of cell phone简单概括了本段内容，是答案。

4、Black HolesMost scientists agree that black holes exist but are nearly impossible to locate. A black hole in the universe is not a solid object, like a planet, but it is shaped like a sphere (球体). Astronomers (天文学家) think that at the center of a black hole there is a single point in space with infinite (无限的) density (稠密).This single point is called a singularity (奇点). If the singularity theory is correct, it means that when a massive star collapses, all the material in it disappears into the singularity. The center of a black hole would not really be a hole at all, but an infinitely dense point. Anything that crosses the black hole is pulled in by its great gravity.Although black holes do exist, they are difficult to observe. These are the reasons,?No light ｏｒanything else comes out of black holes. As a result, they are invisible to a telescope.?In astronomical terms, black holes are truly. Fｏｒexample, a black hole formed by the collapse of a giant star would have an event horizon (视界) only 18 miles across.?The nearest black holes would be dozens of light years away from Earth. One light year is about 6 trillion (万亿) miles. Even the most powerful telescopes could not pick out an object so small at such a great distance.In 1994 the Hubble Space Telescope provided evidence that black holes exist. There are still answers to be found, however, so black holes remain one of the mysteries of the universe. (2007年)The nearest black holes are hundreds of light years away from us.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:B

答案解析:题干大意：离我们最近的黑洞也有几百光年。用中心词nearest定位，原文倒数第二段提到：The nearest black holes would be dozens of light years away from Earth. 离地球最近的黑洞有几十光年(dozens)，而不是“hundreds”。故答案选B。

5、Singing Alarms Could Save the BlindIf you cannot see, you may not be able to find your way out of a burning building ａｎｄ　that could be fatal. A company in Leeds could change all that with directional sound alarms capable of guiding you to the exit. Sound Alert, a company run by the University of Leeds, is installing the alarms in a residential home fｏｒblind people in Sommerｓｅｔａｎｄ　a resource centre fｏｒthe blind in Columbia. The alarms produce a wide range of frequencies that enable the brain to determine where the sound is coming from. Deborah Withington of Sound Alert says that the alarms use most of the frequencies that can be heard by humans. "It\'s a burst of white noise that people say sounds like static on the radio," she says. "Its life-saving potential is great."She conducted an experiment in which people were filmed by thermal-imaging cameras trying to find their way out of a large smoke-filled room. It took them nearly four minutes to find the doｏｒwithout a sound alarm, but only 15 seconds with one. Withington studies how the brain processes sounds at the university. She says that the source of a wide bａｎｄ　of frequencies can be pinpointed more easily than the source of a narrow band. Alarms basedon the same concept have already been installed on emergency vehicles. The alarms will also include rising ｏｒfalling frequencies to indicate whether people should go up ______ down stairs. They were developed with the aid of a large grant from British Nuclear Fuels. 【单选题】

A.or

B.and

C.but

D.otherwise

正确答案:A

答案解析:根据前半句的rising ｏｒfalling frequencies,可以看出这句话也应该填连接词or，表示或者。