The document discusses rules for forming possessive case in English. It notes that names ending in s form the possessive with just an apostrophe, as in "Charles' wife". For singular nouns, the possessive is formed with 's, and for plural nouns it's formed with es'. When multiple people possess the same thing, the possessive 's is added to the last possessor only. When each possessor has their own thing, 's is added to each possessor.