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【单选题】
He()a lot of time in trying to develop the education system in this area.A.
involved
B.
investigated
C.
invested
D.
interfered
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【单选题】Why passengers in a cruise ship sitting in the port of Yokohama were not allowed to leave the ship 14 days ago?
A.
Because all of the passengers in this ship had been infected by new coronavirus.
B.
Because some passenger in this cruise ship were found to have been infected by new coronavirus.
C.
Because they had to be under quarantine.
D.
Because they didn’t want to leave.
【单选题】Why a gearbox is needed in a ship driven by a medium-speed diesel engine? .
A.
To reduce the main engine speed
B.
To increase the main engine speed
C.
To govern the main engine speed
D.
To fix the propeller shaft
【单选题】According to paragraph 1, why is it difficult to determine when the first clipper ship was built?
A.
The clipper predates written records by almost 75 years.
B.
Sailors kept the details of their vessels tightly guarded secrets.
C.
The clipper has no technical specifications that can be used to identify it.
D.
The term 'clipper' was originally used to describe a variety of ships.
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