2021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、The SmogFor over a month, Indonesia was in crisis. Forest fires raged out of control as the country suffered its worst drought for 50 years. Smoke from the fires mixed with sunlight and hot dry air to form a cloud of smog. This pollution quickly spread and within days it was hanging over neighboring countries including Malaysia, Singapore and Thailand. When the smoke combined with pollution from factories and cars, it soon became poisonous. Dangerous amounts of CO became trapped under the smog and pollution levels rose. People wheezed (喘息) and coughed as they left the house and their eyes watered immediately. The smog made it impossible to see across streets and whole cities disappeared as grey soot(烟灰) covered everything. In some areas, water was hosed (用胶管浇) from high-rise city buildings to try and break up the smog. Finally, heavy rains, which came in November. Put out the fires and clear the air. But the environmental costs and health problems will remain. Many people from South-Eastern Asian cities already suffer from breathing huge amounts of car exhaust fumes and factory pollution Breathing problems could well increase and many non-sufferers may have difficulties for the first time. Wildlife has suffered too. In lowland forests, elephants, deer, and tigers have been driven out of their homes by smog. But smog is not just an Asian problem. In fact. was world was first used in London in 1905 to describe the mixture of smoke and thick fog. Fog often hung over the capital. Sometimes the smog was so thick and poisonous that people were killed by breathing problems or in accidents. About 4, 000 Londoners died within five days as a result of thick smog in 1952. The air-pollution index went up to 300 within a few days. 【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:C

答案解析:题句意思是“空气污染指数几天内达到300”。文章根本没有提到此事，故选C。

2、Genetically Modified FoodEuropean Union environmental officials have determined that two kinds of genetically modified corn could harm butterflies, affect food chains and disturb life in rivers and streams, and they have proposed a ban on the sale of the seeds, which are made by Dupont Pioneer, Dow Agrosciences and Syngenta. The preliminary decisions are circulating within the European Commission, which has the final say. Some officials there are skeptical of a ban that would upset the powerful biotechnology industry and could exacerbate tensions with important trading partners like the United States. The seeds are not available on the European market for cultivation.In the decisions, the environment commissioner, Stavros Dimas, contends that the genetically modified corn, or maize could affect certain butterfly species, specifically the monarch, and other beneficial insects. For instance, research this year indicates that larvae of the monarch butterfly exposed to the genetically modified corn "behave differently than other larvae." In the decision concerning the corn seeds produced by Dow and Pioneer, Mr. Dimas calls "potential damage on the environment irreversible." In the decision on Syngenta\'s corn, he says that "the level of risk generated by the cultivation of this product for the environment is unacceptable."A decision by the European Union to bar cultivation of the genetically modified crops would be the first of its kind in the trade bloc, and would intensify the continuing battle over genetically modified corn. Banning the applications for corn crops also would mark a bold new step for European environmental authorities, who are already aggressively pursuing regulations on emissions from cars and aircraft, setting it at odds with the United States and angering industries."These products have been grown in the U. S. and other countries for years," said Stephen Norton, a spokesman for the United States trade representative. "We are not aware of any other case when a product has been rejected after having been reviewed and determined safe by European food safety authorities," he said.Barbara Helfferich, a spokeswoman for Mr. Dimas, declined to comment on the specifics of the procedure because commissioners had not yet made a final decision. But she said that the European Union was within its rights to make decisions based on the "precautionary principle" even when scientists had found no definitive evidence proving products can cause harm. She said that the decisions by Mr. Dimas could go before the commission within a few weeks, but she said that no date had been set. In the decisions, Mr. Dimas cited recent research showing that consumption of genetically modified corn byproducts reduced growth and increased mortality of non-target stream insects and that these insects are important prey for aquatic and riparian predators and that this could have unexpected ecosystem-scale consequences."Although still preliminary, his decisions could drastically tilt the policy against future approvals of genetically modified crops," said Nathalie Moll, a spokeswoman for Europabio, an industry group with 80 members including Syngenta, Pioneer and Dow. Europabio says that the crops grown using the genetically modified corn are already imported into several European countries, including France and Germany, where they are used to feed animals like cows and chickens.Rob Gianfranceschi, spokesman at the United States mission to the European Union in Brussels, said it was too early to comment on a decision that had not yet been formalized. But he made clear that the United States remained frustrated with European policies on genetically modified crops.The word "tilt" (line 1, paragraph 6) most probably means ______.【单选题】

A.incline

B.affect

C.induce

D.evoke

正确答案:A

答案解析:猜词题。根据上下文含义，尽管他的决定还是初步的，但是却会极大地倾向于针对同意未来转基因作物的政策，对比四个选项，只有incline符合此意，故正确答案为A。

3、Radiocarbon DatingNowadays scientists can answer many questions about the past through a technique called radiocarbon (放射性碳), or carbon - 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, or C - 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 detector and 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, or N - 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 for dating 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.Nowadays many scientists depend on radiocarbon for dating age - old objects.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:A

答案解析:本题难度不大，答案依据比较明显，主要答案依据在文章第一段第一段：Now-adays scientists can answer many questions about the past through a technique called radiocarbon，or carbon - 14 dating，谈到现在科学家可以通过一种叫做放射性碳定年法来解读过去，题干是其近义解释，所以正确，答案是A。

4、Radiocarbon DatingNowadays scientists can answer many questions about the past through a technique called radiocarbon (放射性碳), or carbon - 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, or C - 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 detector and 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, or N - 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 for dating 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。

5、The Hurricane1. A hurricane (飓风) is a tropical storm with winds that have reached a constant speed of 74 miles per hour. Hurricane winds blow in a large spiral(螺旋) around a relative calm center known as the "eye". The "eye" is generally 20 to 30 miles wide, and the storm may extend outward 400 miles. As a hurricane nears land, it can bring heavy rains, high winds and storm surges(风暴潮). The storm surges and heavy rains can lead to flooding.2. Hurricanes are given a different label, depending on where they occur. If they begin over the North Atlantic Ocean, the Caribbean Sea, The Gulf of Mexico, or the Northeast Pacific Ocean, they are called hurricanes. Similar storms that occur in the Northwest Pacific Ocean west of the Internaional Date Line are called typhoons near Australia and in the Indian Ocean, they are referred to as tropical cyclones(龙卷风).3. When a hurricane hits land, it can do great damage through its fierce winds, heavy rains, inland(内陆的) flooding and huge waves crashing on to the shore. During a hurricane, homes, businesses and public buildings may be damaged or destroyed, roads and bridges can be washed away. A powerful hurricane can kill more people and destroy more property than any other natural disaster. Fishermen are at special risk from hurricanes as they may be at sea when a hurricane arrives and not be able to get to a safe harbor if they do not receive adequate warning.4. If a hurricane is comming in your area, the most important thing is to stay calm and find shelter immediately. Go to your safe room. If you do not have one, stay indoors during the hurricane and go to a safer place near the center of your home. Cover yourself with a blanket and be sure to keep away from windows and glass doors, because if the glass breaks it’s really dangerous. Do not be fooled if there is lull(暂停), it could be the eye of the storm—winds will pick up again.When a hurricane arrives, fishermen are in great danger if they are at sea and do not get ______.【单选题】

A.different labels

B.window and glass doors

C.inland flooding

D.early warning

E.natural disaster

F.a constant speed

正确答案:D

答案解析:本题有一定难度，需要吃透文章句意，答案依据在文章第三段的倒数第一句：Fisherman are at special risk---they may be at sea-- if they do not receive adequate warning.回来看选项，D项和原文句意相近，是答案。