How do you show possession in a plural noun?

A possessive noun is a noun indicating ownership, possession, origin, or purpose.
A plural possessive noun is a noun for two or more people, places, or things that show possession.
A plural possessive noun is formed by adding an apostrophe (') to the end of plural nouns that already end with -s, or an apostrophe s ('s) to the end of plural nouns that do not end with -s.

Examples:

• The boys' coats all hung in a row. (ownership, the coats belonging to the boys)
• The girls' smiles lit up their faces. (possession, the smiles on the faces of the girls)
• The parents' efforts helped to raise the funds. (origin, the efforts provided by the parents)
• The children's playground was freshly painted. (purpose, the playground intended for children)