2020年職稱英語考試《理工類》考試共65題，分為單選題和多選題和判斷題和計(jì)算題和簡答題和不定項(xiàng)。小編每天為您準(zhǔn)備了5道每日一練題目（附答案解析），一步一步陪你備考，每一次練習(xí)的成功，都會淋漓盡致的反映在分?jǐn)?shù)上。一起加油前行。

1、Radiocarbon Dating
Nowadays 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 (質(zhì)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 (衰減). 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 (宇宙射線). 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 (組織). Once an organism (有機(jī)體) 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.
Radar is used to determine the characteristics of radiocarbon.【單選題】

A.Right

B.Wrong

C.Not mentioned

正確答案:C

答案解析:本題有較大難度，答案依據(jù)不明顯，需要通讀全文作出判斷。通讀全文后可以發(fā)現(xiàn)文章并未提及使用雷達(dá)來進(jìn)行放射性碳測定，所以本題是未提及的，答案是C。

2、A Bad Idea
Think you can walk, drive, take phone calls, e - mail and listen to music at the same time 7 Well, New York's new law says you can't. And you'll be fined $ 100 if you do so on a New York city street. The law went into force last month, following research and a shocking number of accidents that involved people using electronic gadgets (小巧機(jī)械) when crossing the street.
Who's to blame? Scientists say that our multitasking (多任務(wù)處理) abilities are limited. "We are under the impression that our brain can do more than it often can," says Rene Marois, a neuroscientist (神經(jīng)科學(xué)家) in Tennessee. "But a core limitation is the inability to concentrate on two things at once."
The young people are often considered the great multitaskers. However, an Oxford University research suggests this perception is open to question. A group of 18 to 21 years old and a group of 35 to 39 years old were given 90 seconds to translate images into numbers, using a simple code. The younger group did 10 percent better when not interrupted. But when both groups were interrupted by a phone call or an instant message, the older group matched the younger group in speed and accuracy.
It is difficult to measure the productivity lost by multitaskers. Jonathan Spira, chief analyst at Basex, a business - research firm, estimates that the cost of interruptions to the American economy is nearly $ 650 billion a year. _____. The surveys conclude that 28 percent of the workers' time was spent on interruptions and recovery time before they returned to their main tasks.
【單選題】

A.Talking on a cell phone while driving brings you joy anyway.

B.The estimate is based on surveys with office workers.

C.The younger group did 10 percent better when not interrupted.

D.However, an Oxford University research suggests this perception is open to question.

E.Scientists say that our multitasking (多任務(wù)處理) abilities are limited.

F.And you'll be fined $ 100 if you do so on a New York city street.

正確答案:B

答案解析:本題有一定的難度，需要認(rèn)真閱讀文章，理解好句意?？捎门懦ê痛敕ā１绢}的下文談到了對（辦公室）職工做的一次調(diào)查，涉及具體內(nèi)容，所以可以推斷此處應(yīng)該是概括性的句子，來引導(dǎo)下文，而且和職工調(diào)查有關(guān)，回來看選項(xiàng)，把B代入文中，符合邏輯，答案是B。

3、We're happy to report that business is booming this year.【單選題】

A.risky

B.successful

C.failing

D.open

正確答案:B

答案解析:我們很高興地向大家報(bào)告今年業(yè)績紅火。本題難度不大，booming指“景氣，繁榮”，和successful“成功的”是近義詞，A項(xiàng)指“冒險(xiǎn)的”，C項(xiàng)指“衰退的”，D項(xiàng)指“開放的”，都不合句意，最佳答案是B。

4、Some Unusual Celebrations
Some holidays are well - known all around the world. Among them are New Year's Eve celebrations. Also common are days in honor of love and friendship, like Valentine's Day. Each country has its own special holidays too, often to mark important events in its history. Schools, banks and government offices all close on days like these. Some of the days people celebrate, however, are less serious. A few of them are really very strange.
Of course, they are not strange to the people who celebrate them. Perhaps that is because the celebrations have long traditions. Consider April Fool's Day, for example. No one knows when or why it began. Today it is celebrated in many countries—France, England and Australia, among others. On this day, people play practical jokes. Jokes are supposed to be funny, but these jokes do not make everyone laugh. The ones who laugh are the ones playing the jokes. The people they fool often get angry. Does celebrating this day make sense to you?
Dyngus Day in Poland seems strange too. On this day, it is traditional for boys to pour water over the heads of girls. Here is the strangest part, they do it to girls they like.
Other unusual celebrations take place in a single city or town. A holiday called La Tomatina is celebrated in Bunol, Spain. Every year, in late August, big trucks carry more than 200,000 pounds of tomatoes into this little town. Then begins the world-s biggest food fight. For two hours, people in the streets throw tomatoes at each other. Everyone ends up red from head to toe.
August 10 marks the start of the Puck Fair, an Irish festival with a very unusual tradition. People from the town of Killorglin go up into the mountains and catch a wild goat. _____
There are also some celebrations that are really strange. In the United States, sometimes one person gets an idea for a new holiday and tries to get others to accept it. Whose idea was Public Sleeping Day? That one is on February 28. It may seem strange, but it sounds like more fun than the one on February 29. That is supposed to be Toothache Day.
Do you like the idea of inventing a new holiday? If you do, then you will want to mark March 26 on your calendar. That is Make Up Your Own Holiday Day.
【單選題】

A.They bring him back to town, put a crown on his head, and make him king for three days.

B.Some of the days people celebrate, however, are less serious.

C.That is supposed to be Toothache Day.

D.Then begins the world-s biggest food fight.

E.Some people have fun imagining new holidays.

F.Jokes are supposed to be funny, but these jokes do not make everyone laugh.

正確答案:A

答案解析:本題有一定難度，文章此處討論的是愛爾蘭一個(gè)奇怪的節(jié)日，山羊節(jié)，回來看選項(xiàng)，只有A符合上下文邏輯，是答案。

5、The Value of Advertisement
Money spent on advertising is worth spending. It serves directly to bring about a rapid sale of goods at reasonable prices, so setting up a firm home market and making it possible to provide for export at good price. By drawing attention to new ideas it helps greatly to raise standards of living. By helping to increase demand it causes an increased need for labor, and is therefore a nice way to fight unemployment. It lowers the costs of many services: without advertisements your daily newspaper would cost four times as much, the price of your television program would need to be doubled, and travel by bus or subway would cost more.
And perhaps most important of all, advertising provides a promise of reasonable value in the products and services you buy. Besides the fact that twenty-seven Acts of Parliament govern the terms of advertising, no regular advertiser dare produce anything that fails to live up to the promise of his advertisements. He might fool some people for a little while through misleading advertising. He will not do so for long, for the public has the good sense not to buy the poor goods more than once. If you see a product frequently advertised, it is the proof I know that the product does what is promised for it, and that it has good value.
Advertising does more for the good of the public than any other force I can think of.
There is one more point I feel I ought to touch on. Recently I heard a well-known television person declare that he was against advertising because it persuades rather than informs. He was telling us the real difference. Of course advertising tries to persuade.
If its messages were nothing but information, that would be difficult to get more people to buy, for even the choice of the color of a shirt is a bit persuasive-advertising would be so boring that no one would pay any attention. But perhaps that is what the well-known television person wants.
It seems to the writer that____.
【單選題】

A.it is very difficult to get all the information from advertising

B.there is nothing wrong with advertising in persuading the buyers

C.advertising is usually very boring and misleading

D.people will pay attention to the color of a shirt rather than advertising

正確答案:B

答案解析:根據(jù)最后一段，如果廣告只有告知作用而沒有說服作用，人們就不會注意，就不可能有購買欲望。因此選B。