you can overtake on the port side.
you can overtake on the starboard side.
BOAT HANDLING
If it is not possible to overtake on the side requested but
possible on the other side, the boat being overtaken should
reply as follows:
If overtaking is impossible, the boat in front should give 5
short signals.
overtaking impossible.
Blind bends
In certain tight bends, you should announce your presence
with one long blast of your horn.
Navigation lights
Navigation lights should be lit if you navigate after sundown
or in fog.
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