单项选择题
I was told not to use （）in handling bagged cargoes.
A.blocks B.hooks C.cargo sling D.derricks
单项选择题 Before opening the hatch covers, all cleats are to be （）.
单项选择题 A （）is used for lifting long heavy cargo.
单项选择题 （）cargo is unloaded by huge grabs on cranes or by large grain elevators.
