单项选择题
We()a sharp lookout while sailing in the iced waters.
A.keep B.kept C.are keeping D.have kept
单项选择题 When a mis-entry()in the logbook, a red line would be drawn through that part.
单项选择题 (), which consisted of seven short blasts and one prolonged blast, all passengers have to go to their assembly station.
单项选择题 We have just received a message from shore()assistance is on the way.