单项选择题
Do you want the derrick adjusted （）?
A. up and down B. upwards or downwards C. upside or downside D. forwards and backwards
单项选择题 The safe working load of each derrick is five （）.
单项选择题 All the （）in hold No.3 should be bagged.
单项选择题 I was told not to use （）in handling bagged cargoes.
