Bolts, nuts, split pins, hinges, wheels and stoppers should be frequently （）.

Before opening and closing the hatches, the spaces around the covers, all the parts and the gears should be （）.

A.cleared
B.checked
C.removed
D.repaired

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The foreman said three （）would come on board to load cargo.

A.teams
B.parties
C.gangs
D.pairs

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