(By Jakob Lesage): "Passivization is a detransitivizing operation that takes a transitive clause (The dog bites the man.) and turns it into an intransitive clause by promoting the P argument (the man) to morphosyntactic S function. In the resulting intransitive clause, the former A argument (the dog) either vanishes or adopts an oblique function: The man is bitten (by the dog). ‘Mediopassives’, ‘anticausatives’ and the sort (e.g. x breaks the vase > the vase breaks) also count as passives. For languages with multiple passive constructions (e.g. ‘personal’ and ‘impersonal’ passives), this question should be answered 1 if the agent can be overtly expressed in any of these types of passive clauses. If the agent is overtly expressed, it may be unmarked or it may be marked in a number of ways: by case marking or adpositions, word order, etc."