单项选择题
A.calls B.called C.calling D.call
One hour before arrival at Elbe 1 light vessel，masters ...
单项选择题One hour before arrival at Elbe 1 light vessel，masters are advised to contact the pilot boat by（）.
A.telephone B.telegraph C.telex D.VHF
My ship（）that port next month.A.calls atB.has called at...
单项选择题My ship（）that port next month.
A.calls at B.has called at C.call at D.will call at
If you know that the vessel you are about to call on th...
单项选择题If you know that the vessel you are about to call on the VHF radio maintains a radio watch on both the working and the calling frequencies，which frequency should you call on? （）
A.Calling frequency B.Distress frequency C.Urgency frequency D.Working frequency
