Chinese vessels ________ 646,000 square kilometers in the southern Indian Ocean in search of the missing Malaysian flight MH370.
| A．have covered | B．have looked | C．has travelled | D．had searched |
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All passengers ______, please fasten your seat belts and remain seated ______ the plane is landing.
| A．on board; before | B．abroad; since | C．on the board; after | D．aboard; when |
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Unfortunately, it was in Yushu County, ______ a 7.1-magnitude earthquake happened on April 14, 2010, ______ a large number of students were buried inside damaged schools.
| A．which; when | B．that; that | C．where; that | D．where; which |
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______ World Exposition in 2010 is the first registered World Exposition in ______ developing country.
| A．/; a | B．The; a | C．The; / | D．/; the |
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It’s a mistake to think of Chongqing only ______ its tourist attractions.
| A．in addition to | B．by way of | C．in terms of | D．by means of |
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I _____ to telephone you last night, but the line was out of order and I couldn’t get through.
| A．succeeded | B．tried | C．managed | D．failed |