2021年职称英语理工类A级考试真题及答案

1、职称英语理工类A级考试真题及答案 xx年职称英语理工类A级考试真题及答案汇总 115：DBCCA CACCC DABDD 1622：BACBABC 2330：FADB ADEC 3145：DBBDA DADBD CCABA 4650：CDEFA 5165：BADCD _CB ABABA 1. I will not tolerate that sort of behavior in my class. A. control B. observe C. regulate D. aept 2. She showed a natural aptitude for the work. A. sense

2、B. talent C. flavor D. taste 3. Most people find rejection hard to aept. A. excuse B. client C. refusal D. destiny 4. The organization was bold enough to fa _ the press. A. pleased B. powerful C. brave D. sensible 5. They were locked in mortal bat. A. deadly B. open C. actual D. active 6. We were at

3、tracted by the lure of quick money. A. amount B. supply C. tempt D. sum 7. The pro _dures were per _ived as plex and less transparent. A. clear B. ne _ssary C. special D. correct 8. The Stock Exchange is in turmoil following a huge wave of selling. A. Servi _ B. danger C. disorder D. threat 9. He be

4、lieves that Europe must change or it will perish. A. survive B. last C. _ D. move 10. There was a simultaneous trial taking pla _ in the next build. A. fair B. full C .coexisting D. public 11. They promote assimilation of ethnic groups into the _in-stream culture. A. policy B. value C .equality D. i

5、ntegration 12. A sales _ns cardinal rule is to satisfy customers. A. principal B. official C. _ D. legal 13. I must pliment you on your handling of a very difficult situation A. silen _ B. praise C .assure D. plain 14. We lived for years in a perpetual state of fear A. emotional B. nervous C. terrib

6、le D. Continuous 15. The starving children were a pathetic sight. A. mon B. unexpected C. unforgettable D. pitiful Lack of Oxygen Delayed the Rise of Ani _ls on Earth Scientists have long speculated as to why ani _l species didnt flourish sooner, on _ sufficient oxygen covered the Earths su _ _. Ani

7、 _ls began to prosper at the end of the Proterozoic period, about 800 million years ago but what about the billion-year stretch before that, when most researchers think there also was plenty of oxygen? Well, it seems the air wasnt so great then, after all. In a study published Oct. 31 in Scien _, Ya

8、le researcher Noah Planavsky and his colleagues found that oxygen levels during the “boring billion” period were only 0.1% of what they are today. In other words, Earths atmosphere couldnt have supported a diversity of creatures, no _tter what geic advan _ments were poised to our. “There is no quest

9、ion that geic and ecological innovation must ulti _tely be behind the rise of ani _ls, but it is equally unavoidable that ani _ls need a _rtain level of oxygen,” said Planavsky, co-lead author of the research along with Christopher Reinhard of the Georgia Institute of Technology. “Were providing the

10、 first eviden _ that oxygen levels were low enough during this period to potentially prevent the rise of ani _ls.” The scientists found their eviden _ by _yzing chromium (Cr) isotopes in ancient sediments from China, Australia, Canada, and the United States. Chromium is found in the Earths continent

11、al crust, and chromium oxidation is directly linked to the presen _ of free oxygen in the atmosphere. Specifically, the team stu _d samples deposited in shallow, iron-rich o _an areas, near the shore. They pared their data with other samples taken from younger locales known to have higher levels of

12、oxygen. Oxygens role in controlling the first appearan _ of ani _ls has long vexed scientists. “We were missing the right approach until now,” Planavsky said. “Chromium gave us the proxy.” Previous esti _tes put the oxygen level at 40% of todays conditions during pre-ani _l times, leaving open the p

13、ossibility that oxygen was already plentiful enough to support ani _l life. In the new study, the researchers acknowledged that oxygen levels were “highly dynamic” in the early atmosphere, with the potential for oasional spikes. However, they said, “It seems clear that there is a first-order differen _ in the nature of Earth su _ _ Cr cycling” before and after the rise of ani _ls. “If we are right, our results will really change how people vie