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單項(xiàng)選擇題

To ensure the safety in operating hatch covers, oil the moving parts （）.

A. monthly
B. every three months
C. once monthly
D. every two months

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單項(xiàng)選擇題

During operation, the （）should check the working condition of the derrick.

A.foreman
B.operator
C.opener
D.stevedore

單項(xiàng)選擇題

（）has more than ten percent broken wires. Stop using it at once.

A. The cargo runner
B. The cargo block
C. The derrick sling
D. The lashing wire

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