Word 1: Sane (SAYN)
Meaning 1: Proceeding from a sound mind.
Example Sentence: The only sane decision was to quit the job.

Word 2: Seine (SAYN)
Meaning 1: A large net with sinkers on one edge and floats on the other that hangs vertically in the water and is used to enclose and catch fish when its ends are pulled together or are drawn ashore.
Example Sentence: The fishermen waited with their seines to catch the fish after dark.

Meaning 2: Fish (an area) with a seine.
Example Sentence:The coastline was full of fishermen with their boats and seines.

Word 3:Seine (SAYN, SEN)
Meaning 1: River 480 miles (772 kilometers) N France flowing NW into Bay of the Seine (inlet of English Channel).
Example Sentence: We had a pleasant time going down the river Seine in a boat.

Example Sentence using both words:
It was a sane decision which he took to go down the River Seine which flows for 13kms through Paris, and then on to the harbor and hire a boat and a seine to spend the entire holiday fishing.