Direct-inverse language

The definition of a direct–inverse language is a matter under research, but it is widely understood to involve different grammar for transitive predications according to the relative positions of their "subject" and their "object" on a person hierarchy, which, in turn, is some combination of saliency and animacy specific to a given language. The direct construction is the unmarked one. The direct construction is used when the subject of the transitive clause outranks the object in the person hierarchy, and the inverse is used when the object outranks the subject. The existence of direct–inverse morphosyntax is usually accompanied by proximate–obviative morphosyntax. The direct–inverse dimension subsumes the proximate–obviative dimension. Across languages, obviation almost always involves the third person, but second-person obviation is reported for some Nilo-Saharan languages), and the direct–inverse alternation is usually presented as being a way of marking the proximate–obviative distinction between two (or more) third person arguments of a sentence. However, there are at least two languages with inverse systems, the Mesoamerican languages Zoque and Huastec, in which inverse morphosyntax is never used when both subject and object are third person, but only when one of these arguments is third person and the other is a speech act participant (SAP), the first or second person .

Neither a morphological feature nor a syntactic feature is common to all inverse systems.

Direct-inverse systems on verbs coexist with the various morphosyntactic alignments in nouns. In some inverse languages, including all Mesoamerican inverse languages, the direct-inverse alternation changes the morphosyntactic alignment, and the language is said to have hierarchical alignment.

Klaiman has suggested four common properties of inverse languages:

Some languages that comply with Klaiman's definition of an inverse language are Maasai, Carib, Wastek, Chukchee, the Algonquian languages and some Athapaskan languages like Koyukon and Navajo, Mapudungun and Movima (language isolates), rGyalrong (Sino-Tibetan) and some Mixe–Zoquean languages. On the other hand, the Mixean language Oluteco has been reported to have an inverse system which does not conform to the second rule, as certain intransitive verbs and passives of ditransitives also can take inverse morphology.

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