absolutive case vs ergative case

absolutive case

noun
  • case used to indicate the patient or experiencer of a verb’s action. The absolutive case is used to mark the subject of an intransitive verb, as well as the object of a transitive verb (inasmuch as they are codified in the English nominative-accusative system). Some languages that employ the absolutive case include Abkhaz, Basque, Chechen, Dyirbal, Hindi, Inuktitut, Hiligaynon, and Yup'ik. 

ergative case

noun
  • A grammatical case used to indicate the agent of a transitive verb in ergative-absolutive languages. 

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