large oars or pieces of wood at the back of the ship used for steering
# the foresail
"the sail at the front of the ship." The sail was a large piece of cloth that catches the wind to move the ship.
# they headed to the beach
"they steered the ship toward the beach"
# they came to a place where two currents met
A current is water flowing in one continuous direction. Sometimes more than one water current can flow across another. This may cause the sand under the water to pile up making the water more shallow.