Plural nouns not ending in s take ’s in the possessive.
Examples:
- the firemen’s ball,
- the policemen’s quarters,
- the children’s hour.
Note. In older English the possessive of most nouns was written as well as pronounced with the ending -es or -is. Thus, in Chaucer, the possessive of child is childës or childis; that of king is kingës or kingis; that of John is Johnës or Johnis. The use of an apostrophe in the possessive is a comparatively modern device, due to a misunderstanding. Scholars at one time thought the s of the possessive a fragment of the pronoun his; that is, they took such a phrase as George’s book for a contraction of George his book. Hence they used the apostrophe before s to signify the supposed omission of part of the word his. Similarly, in the possessive plural, there was thought to be an omission of a final es; that is, such a phrase as the horses’ heads was thought to be a contraction of the horseses heads. Both these errors have long been exploded.
91. Nouns like sheep and deer, which have the same form in both the singular and the plural, usually take ’s in the possessive plural.
Thus, the deer’s tracks would be written, whether one deer or more were meant.
92. Possessive Singular of Nouns ending in s.
1. Monosyllabic nouns ending in s or an s-sound usually make their possessive singular by adding ’s.
Examples:
- Charles’s hat,
- Forbes’s garden,
- Mr. Wells’s daughter,
- Rice’s carriage,
- Mrs. Dix’s family,
- a fox’s brush.