Case Marking: The grammatical system that uses inflections or particles to indicate the syntactic and semantic roles of nouns in a sentence.
Ergativity: A type of alignment system where the subject of an intransitive verb is treated like the object of a transitive verb, differing from the nominative-accusative system.
Nominative-Accusative: An alignment system where the subject of both transitive and intransitive verbs is treated the same (nominative), while the object of transitive verbs is marked differently (accusative).