单项选择题
A. cargo winch B. lift winch C. derrick D. crane
Rubbish can be thrown into the water （）.A. in a harbour...
单项选择题Rubbish can be thrown into the water （）.
A. in a harbour B. in any place C. 25 miles off the land D. 10 miles off the land
The jumbo boom can （）.A. lift heavy cargoB. load and un...
单项选择题The jumbo boom can （）.
A. lift heavy cargo B. load and unload C. join ropes together D. lift light cargo
We are （）the cargo wire.A.greasingB.greaseingC.greasedD...
单项选择题We are （）the cargo wire.
A.greasing B.greaseing C.greased D.greaser
