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單項(xiàng)選擇題

Wire ropes should be greased （）.

A. every month
B. every two months
C. every three months
D. A or B

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單項(xiàng)選擇題

The （）of the derrick is 5 tons.

A.GT
B.SWL
C.DWT
D.TDW

單項(xiàng)選擇題

Have you got （）lashing wires?

A.plenty
B.much
C.a lot
D.enough

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