This document provides rules for making nouns plural or possessive in English. It explains that most singular nouns form the plural by adding 's', but there are exceptions for nouns ending in letters like x, ch, sh where 'es' is added instead. It also covers forming the possessive case, noting that for singular nouns an apostrophe s is added, while for plural nouns ending in s just an apostrophe is added and for other plurals apostrophe s is added.