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、Seeing Red Means Danger AheadThe colｏｒred often means danger ａｎｄ　by paying attention, accidents can be prevented. In the future, the colｏｒred also may help prevent danger at construction sites. Thanks to new work by engineers, bridge supports ｏｒother kinds of materials, could one day contain a colｏｒ- changing material. It will turn red before a structure collapses ｏｒfalls apart.The secret behind the colｏｒ- changing material is a particular type of molecule (分子). A molecule is aｇｒｏｕｐof atoms (原子) held together by chemical bonds. Molecules come in all shapes ａｎｄ　sizes ａｎｄ　make up everything you can see, touch ｏｒfeel. How a molecule behaves depends on what kinds of atoms it contains ａｎｄ　how they\'re held together.When a polymer (聚合物) containing a colｏｒ- changing molecule called a mechanophore (机械响应性聚合物) is about to break, it produces a color. When a polymer with mechanophore molecules becomes "injured" ｏｒweak, one of the mechanophore bonds breaks ａｎｄ　the material turns red. "It\'s a really simple detection method," says Nancy Sottos, one of the scientists who worked on the project. Sottos ａｎｄ　her team tested the colｏｒ- changing polymers in their lab. The test results proved encouraging.There is a way to get rid of the red colｏｒlight. When a bright light is shone on the mechanophore, the broken bond is fixed ａｎｄ　the red colｏｒdisappears. Thus "self - healing" may be a problem fｏｒengineers. They need to use the colｏｒ- changer in big construction projects that will be outside, under sunlight. ａｎｄ　sunlight will make the mechanophore\'s warning system _____.Sottos ａｎｄ　her fellow scientists still have a lot of work to do before the colｏｒ- changing molecules can be used outside the lab.【单选题】

A.dangerous

B.useless

C.helpful

D.important

正确答案:B

答案解析:本题有一定难度，干扰项干扰较大，关键在理解好文章上下文意义，文章此处是说“阳光会让这种机械响应性聚合物的报警系统失效”，答案是B。

2、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!Cell phones are common in our lives ａｎｄ　have become ______.【单选题】

A.a necessity

B.an emergency

C.a number of new headaches

D.family arguments

E.big ａｎｄ　light palm - sized models

F.countless new facilities

正确答案:A

答案解析:本题难度不大，虽然答案依据不太明显，但第二段的主旨句可以看做是答案依据，通读第二段，可以判断出手机已成一个必需的工具，所以答案是A。

3、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。

4、Greene spent a brief time at Cambridge.【单选题】

A.hard

B.good

C.short

D.long

正确答案:C

答案解析:格林在剑桥做了简短停留。本题难度不大，干扰项干扰不大，是送分题，可以确认brief和short都是“简短的”意思，答案是C。

5、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.Liquid water only exists ______.【单选题】

A.in the center of the earth

B.on the surface of our planet

C.in a very narrow range of temperatures

D.in the coastal areas of the earth

正确答案:C

答案解析:本题难度不大，答案依据比较明显，答案依据是文章第一段第二句，谈到液态水只存在于很小的温度范围内（零度到一百度），回来看选项，C项是其近义解释，所以正确，答案是C。