单项选择题
A.embark B.embarkation C.disembark D.B+C
The boat is （）to the water surface.A.downB.topC.lowerD....
单项选择题The boat is （）to the water surface.
A.down B.top C.lower D.up
Ready for （）the boat.A.lowerB.loweringC.loweredD.topped
单项选择题Ready for （）the boat.
A.lower B.lowering C.lowered D.topped
We are going to carry out an emergency （）.A.practiseB.p...
单项选择题We are going to carry out an emergency （）.
A.practise B.practice C.drill D.drills
