The Deck Riddle

We travelled the sea far and wide. At one time, two of my sailors were
standing on opposite sides of the ship. One was looking west and the
other one east. And at the same time, they could see each other clearly.
How can that be possible?

Answer:

One sailor was on the east side looking west; the other was on the west side looking east — so they were facing each other across the deck.

Explanation:
“Opposite sides” means port and starboard. If the sailor on the east side looks west and the one on the west side looks east, their lines of sight meet in the middle, so they see each other.