单项选择题
They are towed into positions and anchored there.（）
A.他们就位后抛锚。 B.他们被拖到位后在那里抛锚。 C.拖轮就位后抛锚。 D.把拖轮拖到位后在那里抛锚。
单项选择题 Ro/Ro ships have doors at the bow or stern.（）
单项选择题 Liners sail on regular routs and keep to a fixed timetable.（）
单项选择题 Ships can be classified according to what they carry.（）
