单项选择题
The ship is now down()head.
A.on B.by C.in D.for
单项选择题 The ship is not very stable,please()when making a turn.
单项选择题 The radiotelegraphy safety messages for condition indicating distress,urgency and safety,respectively,are().
单项选择题 The most likely time for oil pollution while bunkering is when().