The seaman has sailed on many seas.

Marine resources are essential for ecological balance.

The sailor sailed the seas for years.

Scientists have discovered new species on the seabed.

The saltwater crocodile is the largest living reptile on Earth.

San Marino is a small landlocked state in Italy.

He covered a thousand nautical miles during the race.

The underwater is a fascinating technology.

The submarine dives into the depths of the ocean.

This landlubber doesn't know how to navigate on the high seas.