To show possession with regular plural nouns add an apostrophe at the end.
Compare:
- Airplane’s wings.
(one airplane + apostrophe + s) - Airplanes’ wings.
(many airplanes + s + apostrophe)
As in these examples:
- The cats’ beds.
- Two-year olds’ activities.
To show possession with irregular plural nouns add an apostrophe and -s at the end.
Compare:
- Your child’s toys.
(one child + apostrophe + s)
Your children’s toys.
(many children + apostrophe + s)
As in these examples:
- The sheep’s wool.
(one sheep)
The sheep’s wool.
(many sheep) - Father-in-law’s duties.
(one father-in-law)
Fathers-in-law’s duties.
(many fathers-in-law)
If many nouns possess another noun then only the last noun is in the possessive form.
- Juliet, Romeo and William’s holiday is next week.
(They will all go on holiday together next week.) - William and Mary’s house is at the end of the street.
If many nouns possess their own noun then all of the nouns will be in the possessive form.
- Juliet’s, Romeo’s and William’s holidays are next week.
(They will all go on different holidays next week.) - William’s and Mary’s houses are next to each other.
