单项选择题
A.vessel on her port side that is crossing her course
B.vessel that is overtaking her
C.seaplane on the water
D.sailing vessel
单项选择题 It has often been stressed in the Courts that the look-out man should，preferably，be stationed forward，unless weather conditions make this（）.
单项选择题 In the daytime，you see a large sailing vessel on the beam. You know that she is also propelled by machinery if she shows（）.
单项选择题 In restricted visibility the speed of a vessel without operational radar may be（）enable effective avoiding action to be taken on sighting another ship.