The document discusses case systems in three languages: Pitta-Pitta, Latin, and English.
Pitta-Pitta has a complex case system with suffixes that mark relations between nouns and verbs. Latin also has a complex case system with different declensions for nouns. English once had cases but over time lost most of its case system, retaining it only for pronouns and the genitive possessive case.
The document also defines nine case categories - agentive, benefactive, comitative, dative, factitive, objective, ergative, instrumental, and locative - and provides examples of how they function in sentences.