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2014年職稱英語考試?yán)砉ゎ怉級模擬沖刺題二2.2

發(fā)布時間:2014-02-17 共4頁

  Earth's Inner Core

  Scientists have long struggled to understand what lies at the planet's center, Direct observation of its center is impossible, so researchers must (51)_________ to other evidence.

  In 1889, a German scientist detected a severe earthquake in Japan. Geophysicistsconcluded that shock waves (52) _________ jolts (晃動) from one side of Earth through the centerto the other side. Then in 1936, Danish geophysicist Inge Lehmann studied the waves (53)_________to determine that within Earth's core of molten (熔化了的) iron lies a solid inner core-but(54) _________that core was made of eluded (難倒) her. Other geophysicists quicklydetermined that Lehmann's inner core was composed mostly(55)_________iron. Since then,Lehmann's discovery has (56) _________conventional Earth science.

  But now scientists are challenging traditional theory with new and radical (57)_________. Forexample, Earth's center could actually contain an "inner core within the inner core, claim Ishiiand colleague Adam Dziewonski. Analyzing hundreds of thousands of earthquake wave(58)_________, they maintain that the inner core has at its heart a tiny, even more solid sphere(球體) . This sphere "may be the oldest fossil (59)_________ from the formation of Earth," saysDziewonski.

  Dziewonski and Ishii speculate that shortly (60)_________ earth formed around 4.8billionyears ago, a giant asteroid (小行星) smashed into the young planet and nearly melted it. ButEarth's center didn't quite melt; it (61) _________ mass as the planet cooled. The core within acore may be the kernel (核心) that endured. "Its presence could change our basic ideas about the(62) _________ of the planet, " Dziewonski says idea is tame (溫和的) compared to the(63)_________ theories of independent geophysicist J. Marvin Herndon. Earth's inner core ismade not of iron, he claims but a(64)_________ of nickel and silicon Hemdon has a trulyrevolutionary notion: Within the nickel silicide (硅化物) inner core is also an "inner" innercore an 8 km -- wide ball of the element uranium. Uranium is radioactive. Hemdon thinksthe uranium releases heat energy as its atoms(65)_________ fission-split and crash into another in achain reaction. In other words, we may live on top of a gigantiC. "natural" nuclear powerplant.

  請在第__(51)__處填上正確答案。

  A.try

  B.leave

  C.turn

  D.point

  52、請在第__(52)__處填上正確答案。

  A.create

  B.receive

  C.feel

  D.overcome

  53、請在第__(53)__處填上正確答案。

  A.work

  B.solution

  C.job

  D.patterns

  54、請在第__(54)__處填上正確答案。

  A.whether

  B.what

  C.why

  D.how

  55、請在第__(55)__處填上正確答案。

  A.from

  B.within

  C.of

  D.to

  56、請在第__(56)__處填上正確答案。

  A.followed

  B.dominated

  C.restored

  D.opposed

  57、請在第__(57)__處填上正確答案。

  A.ideas

  B.demands

  C.phenomena

  D.movements

  58、請在第__(58)__處填上正確答案。

  A.things

  B.acts

  C.methods

  D.records

  59、請在第__(59)__處填上正確答案。

  A.taken

  B.benefited

  C.left

  D.kept

  60、請在第__(60)__處填上正確答案。

  A.after

  B.before

  C.since

  D.when

  61、請在第__(61)__處填上正確答案。

  A.expanded

  B.modified

  C.gained

  D.melted

  62、請在第__(62)__處填上正確答案。

  A.size

  B.origin

  C.structure

  D.shape

  63、請在第__(63)__處填上正確答案。

  A.radical

  B.traditional

  C.classical

  D.conventional

  64、請在第__(64)__處填上正確答案。

  A.system

  B.copy

  C.model

  D.compound

  65、請在第__(65)__處填上正確答案。

  A.charge

  B.last

  C.experience

  D.show

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