Impersonal passive voice

The impersonal passive voice is a verb voice that decreases the valency of an intransitive verb (which has valency one) to zero.^[1]^: 77

The impersonal passive deletes the subject of an intransitive verb. In place of the verb's subject, the construction instead may include a syntactic placeholder, also called a dummy. This placeholder has neither thematic nor referential content. (A similar example is the word "there" in the English phrase "There are three books.")

In some languages, the deleted argument can be reintroduced as an oblique argument or complement.

^ Dixon, R. M. W. & Alexandra Aikhenvald (1997). "A Typology of Argument-Determined Constructions". In Bybee, Joan, John Haiman, & Sandra A. Thompson (eds.) Essays on Language Function and Language Type: Dedicated to T. Givón. Amsterdam: John Benjamins, 71–112.

[DixAikh1997-1] Dixon, R. M. W. & Alexandra Aikhenvald (1997). "A Typology of Argument-Determined Constructions". In Bybee, Joan, John Haiman, & Sandra A. Thompson (eds.) Essays on Language Function and Language Type: Dedicated to T. Givón. Amsterdam: John Benjamins, 71–112.

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