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1、2022年考博英语-武汉大学考前拔高综合测试题（含答案带详解）1. 不定项选择题Asteroids and comets that repeatedly smashed into the early Earth covered the planets surface with molten rock during its earliest days, but still may have left oases of water that could have supported the evolution of life, scientists say. The new study revea
2、ls that during the planets infancy, the surface of the Earth was a hellish environment, but perhaps not as hellish as often thought, scientists added.Earth formed about 4.5 billion years ago. The first 500 million years of its life are known as the Hadean Eon. Although this time amounts to more than
3、 10 percent of Earths history, little is known about it, since few rocks are known that are older than 3.8 billion years old.For much of the Hadean, Earth and its sister worlds in the inner solar system were pummeled with an extraordinary number of cosmic impacts. “It was thought that because of the
4、se asteroids and comets flying around colliding with Earth, conditions on early Earth may have been hellish,” said lead study author Simone Marchi, a planetary scientist at the Southwest Research Institute in Boulder, Colorado. This imagined hellishness gave the eon its nameHadean comes from Hades,
5、the lord of the underworld in Greek mythology.However, in the past dozen years or so, a radically different picture of the Hadean began to emerge. Analysis of minerals trapped within microscopic zircon crystals dating from this eon “suggested that there was liquid water on the surface of the Earth b
6、ack then, clashing with the previous picture that the Hadean was hellish,” Marchi said. This could explain why the evidence of the earliest life on Earth appears during the Hadeanmaybe the planet was less inhospitable during that eon than previously thought.The exact timing and magnitude of the impa
7、cts that smashed Earth during the Hadean are unknown. To get an idea of the effects of this bombardment, Machi and his colleagues looked at the moon, whose heavily cratered surface helped model the battering that its close neighbor Earth must have experienced back then.“We also looked at highly side
8、rophile elements (elements that bind tightly to iron), such as gold, delivered to Earth as a result of these early collisions, and the amounts of these elements tells us the total mass accreted by Earth as the results of these collisions,” Marchi said. Prior research suggests these impacts probably
9、contributed less than 0.5 percent of the Earths present-day mass.The researchers discovered that “the surface of the Earth during the Hadean was heavily affected by very large collisions, by impactors larger than 100 kilometers or so really, really big impactors,” Marchi said. “When Earth has a coll
10、ision with an object that big, that melts a large volume of the Earths crust and mantle, covering a large fraction of the surface,” Marchi added. These findings suggest that Earths surface was buried over and over again by large volumes of molten rock enough to cover the surface of the Earth several
11、 times. This helps explain why so few rocks survive from the Hadean, the researchers said.1.Why is it little known about the Earths first 500 million years?2.Why is the early Earth imagined to be hellish?3.Why was the early Earth in fact less inhospitable than often thought?4.How can the moon help w
12、ith the understanding of the impacts that smashed the Earth?问题1选项A.Because it is an imagined period of time.B.Because this period is of little significance.C.Because it is impossible to know about this period.D.Because no rocks are available as research evidence.问题2选项A.Because it was often smashed b
13、y asteroids and comets.B.Because back then Hades, the lord of Hell, resigned.C.Because it was so according to Greek mythology.D.Because back then there was no life.问题3选项A.Because minerals of the Hadean have been found suggesting the existence of life.B.Because the clashing brought by asteroids and c
14、omets was not completely damaging.C.Because during the Hadean there already existed the evidence of life.D.Because there had already been liquid water on the Earth back then.问题4选项A.The moon once smashed into the Earth too.B.The moon was battered earlier than the Earth.C.The moon, as a close neighbor
15、, is easier to observe.D.The moons surface is heavily cratered as the Earths.【答案】第1题:D第2题:A第3题:D第4题:D【解析】第1题:1.【选项释义】1. Why is it little known about the Earths first 500 million years? 1. 为什么人们对地球最初的5亿年知之甚少？A. Because it is an imagined period of time. A. 因为这是一段想象的时间。B. Because this period is of litt
16、le significance. B. 因为这个时期的意义不大。C. Because it is impossible to know about this period. C. 因为要了解这个时期是不可能的。D. Because no rocks are available as research evidence. D. 因为没有岩石可以作为研究证据。【考查点】事实细节题。【解题思路】根据第二段最后一句“尽管这段时间占地球历史的10%以上，但我们对它知之甚少，因为我们所知的岩石中很少有年龄超过38亿年的（few rocks are known）”，理解可知，人们对地球最初的5亿年知之甚少是因为所知的岩石年龄很少超过38亿年，也就是说我们没有岩石
