Paper or Plastic ?
Take a walk along the Chesapeake Bay，and you are likely to see plastic bags floating in the water.They have made their (51)into local waterways and, from there，into the bay，where they can (52)wildlife.Piles of them show up in landfills(垃圾填埋地)and on city streets.Plastic bags also take an environmental toll(代价)in the (53)of millions of barrels of oil expended every year to produce them.
Enter Annapolis and you will see plastic bags (54)free in department stores and supermarkets.Alderman(市议员)Sam Shropshire has introduced a well-meaning
(55)to ban retailers from distributing plastic shopping bags in Maryland's capital.Instead, retailers would be required to (56)bags made of recycled paper and to sell reusable bags.The city of Baltimore is (57)a similar measure.Opponents of the (58)，however, argue that paper bags are harmful, too：They cost more to make, they (59)more resources to transport, and recycling them causes more pollution than recycling plastic.The argument for depriving Annapolis residents (60)their plastic bags is far from accepted.Everyone in this (61)is right about one thing：Disposable shopping bags Of any type are wasteful，and the best outcome would be for customers to (62)bags instead.Annapolis's mayor is investigating how to hand out free, reusable shopping bags to city residents, a proposal that can proceed (63)of whether other bags are banned.A less-expensive alternative would be to encourage retailers to give (64)to customers who bring their own reusable bags.And this policy would be more (65)if stores imitated furniture mega-retailer(超大零售商)Ikea and charged for disposable bags at the checkout counter.A broad ban on the use of plastic shopping bags is not the answer.
51 A difference B point C progress D way
52 A harm B help C keep D protect
53 A light B form C time D place
54 A dropped B packed C put D distributed
55 A proposal B service C system D change
56 A open B fill C offer D hold
57 A getting B considering C replacing D improving
58 A idea B effect C technology D behavior
59 A limit B provide C destroy D consume
60 A from B with C of D in
61 A debate B organization C project D program
62 A reform B reuse C repair D reduce
63 A instead B because C regardless D careless
64 A examples B instructions C discounts D receipts
65 A impressive B effective C formal D typical
答案：
51.D 52.A 53.B 54.D 55.A
56.C 57.B 58.A 59.D 60.C
61.A 62.B 63.C 64.C 65.B
German scientist detected a severe earthquake in Japan
Scientists have long struggled to understand what lies at the planet's center. Direct observation of its center is impossible, so researchers must (1) to other evidence.
In 1889, a German scientist detected a severe earthquake in Japan. Geophysicists concluded that shock waves (2) jolts (晃动) from one side of Earth through the center to the other side. Then in 1936, Danish geophysicist Inge Lehmann studied the waves' (3) to determine that within Earth's core of molten (熔化了的) iron lies a solid inner core - but (4) that core was made of eluded (难倒) her. Other geophysicists quickly determined that Lehmann's inner core was composed mostly (5) iron. Since then, Lehmann's discovery has (6) conventional Earth science.
But now scientists are challenging traditional theory with new and radical (7). For example, Earth's center could actually contain an "inner core within the inner core," claim Ishii and colleague Adam Dziewonski.
Analyzing hundreds of thousands of earthquake wave (8), they maintain that the inner core has at its heart a tiny, even more solid sphere (球体). This sphere "may be the oldest fossil (9) from the formation of Earth," says Dziewonski.
Dziewonski and Ishii speculate that shortly (10) Earth formed around 4.8 billion years ago, a giant asteroid (小行星) smashed into the young planet and nearly melted it. But Earth's center didn't quite melt; it (11) mass as the planet cooled. The core within a core may be the kernel (核心) that endured. "Its presence could change our basic ideas about the (12) of the planet," Dziewonski says.
Dziewonski's idea is tame (温和的) compared to the (13) theories of independent geophysicist J. Marvin Herndon. Earth's inner core is made not of iron, he claims, but a (14) of nickel and silicon. Herndon has a truly revolutionary notion: Within the nickel silicide (硅化物) inner core is also an "inner" inner core - an 8 km-wide ball of the element uranium. Uranium is radioactive. Herndon thinks the uranium releases heat energy as its atoms (15) fission-split and crash into one another in a chain reaction. In other words, we may live on top of a gigantic, "natural" nuclear power plant.
1 A try B leave C turn D point
2 A create B receive C feel D overcome
3 A work B solution C job D patterns
4 A whether B what C why D how
5 A from B within C of D to
6 A followed B dominated C restored D opposed
7 A ideas B demands C phenomena D movements
8 A things B acts C methods D records
9 A taken B benefited C left D kept
10 A after B before C since D when
11 A expanded B modified C gained D melted
12 A size B origin C structure D shape
13 A radical B traditional C classical D conventional
14 A system B copy C model D compound
15 A charge B last C experience D show
参考答案:
1. C 2. A 3. D 4. B 5. C
6. B 7. A 8. D 9. C 10. A
11. C 12. B 13. A 14. D 15. C
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