单项选择题
Please stand-by（）channel 12.
A.to B.on C.at D.in
单项选择题 Please use these bags to make a wall in the hold and leave the（）for ballasting.
单项选择题 The check under shipowner’s organization made at the loading port is to avoid accepting cargo（）upon receipt.
单项选择题 The chief officer estimated the broken space（）3500 cubic feet.
