Active–stative

An active–stative language (active language for short), also commonly called a split intransitive language, is a language in which the sole argument ("subject") of an intransitive clause (often symbolized as S) is sometimes marked in the same way as an agent of a transitive verb (that is, like a subject such as "I" or "she" in English) but other times in the same way as a direct object (such as "me" or "her" in English).

The case or agreement of the intransitive argument (S) depends on semantic or lexical criteria particular to each language. The criteria tend to be based on the degree of volition or control over the verbal action exercised by the participant.

For example, if one tripped and fell, an active–stative language might require them to say the equivalent of "fell me." To say "I fell" would mean that the person had done it on purpose, such as taking a fall in boxing. Another possibility is empathy; for example, if someone's dog were run over by a car, one might say the equivalent of "died her." To say "she died" would imply that the person was not affected emotionally.

If the core arguments of a transitive clause are termed A (agent of a transitive verb) and O (object, or patient of a transitive verb), active–stative languages can be described as languages that align intransitive S as S = O ("me fell") or S = A ("I fell"), depending on the criteria described above.

Active–stative languages contrast with accusative languages such as English that generally align S as S = A, and to ergative languages that generally align S as S = O.

For most such languages, the case of the intransitive argument is lexically fixed for each verb, regardless of the actual degree of volition of the subject but often corresponding to the most typical situation. For example, the argument of swim may always treated like the transitive subject (agent-like), and the argument of sleep like the transitive direct object (patient-like). In Dakota, arguments of active verbs such as to run are marked like transitive agents, as in accusative languages, while arguments of inactive verbs such as to stand are marked like transitive objects, as in ergative languages. In a language like this, if the subject of a verb like run or swallow is defined as agentive, it will be always marked so, even if the action of swallowing is involuntary. This subtype is sometimes known as split-S.

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