| add_irregular_rule | Add a custom rule for making "deregularizing" a word |
| add_plural_rule | Add a custom rule for making a word plural |
| add_singular_rule | Add a custom rule for making a word singular |
| add_uncountable_rule | Make a word "uncountable" |
| is_plural | Test plural state of a word |
| is_singular | Test plural state of a word |
| pluralize | Pluralize a word |
| singularize | Singularize a word |