單項選擇題Sometimes lights are()by fog,haze,dust,smoke,or precipitation which may be present at the light,or between the light and the observer,and which is possibly unknown by the observer.

A.obscured
B.darkened
C.greyed
D.delighted


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1.單項選擇題Pilotage in this country is().

A.Free of charge
B.Important
C.Required
D.Unnecessary

3.單項選擇題If the winch should fail while you are hauling in the anchor,what prevents the anchor cable from running out().

A.Chain stopper
B.Devil's claw
C.Hawse ratchet
D.Riding pawl

4.單項選擇題If the ship is alongside the wharf,what kind of()is used?

A.pilot ladder
B.rope ladder
C.rod ladder
D.accommodation ladder

5.單項選擇題If a ship has sternway,with accommodation block aft,she may settle with the wind().

A.on her beam
B.on her stern
C.on her bow
D.broad on the quarter