The Lingua::EN::Inflect::Number module extends the functionality of Lingua::EN::Inflect (the liblingua-en-inflect-perl package) with three new functions. . number() takes a word, and determines its number. It returns whether the word is singular, plural, or ambiguous for words that can be either singular or plural. . Based on the number() function there are to_S() and to_PL() which take a word and convert it forcefully either to singular or to plural. In Lingua::EN::Inflect funny things happen if you try to pluralise an already-plural word, but this module does the right thing.