单项选择题
You should release the （）(重型螺栓)on top of the cover.
A. lock in B. heavy bolt C. socket D. heavy cleat
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.
单项选择题 After operation, drop the control levers into stowing hole, and （）(停止)the electric motor.
