单项选择题
A. the guide rail B. the guide rope C. the side coaming D. the guide roller
Could you show me （）to open the hatch covers?A.whyB.whe...
单项选择题Could you show me （）to open the hatch covers?
A.why B.when C.how D.what
If the hatch cover does not move, （）should be checked.A...
单项选择题If the hatch cover does not move, （）should be checked.
A. the open valve B. the stop valve C. the steam valve D. the close valve
To ensure the safety in operating hatch covers, oil the...
单项选择题To ensure the safety in operating hatch covers, oil the moving parts （）.
A. monthly B. every three months C. once monthly D. every two months
