单项选择题
A （）(重吊杆)is used for lifting long heavy cargo.
A. derrick B. crane C. jumbo boorn D. special crane
单项选择题 You should release the （）(重型螺栓)on top of the cover.
单项选择题 The sailor should （）(报告)it to the duty officer.
单项选择题 The running wheel runs along the （）(导轨)on the hatch coaming top.
