The acquisition of the causative alternation in Thai

A study was undertaken to find out if children acquiring Thai overgeneralize the causative alternation, and if they do, why they do it and how they unlearn it. Data were collected from a longitudinal study of one child and a cross-sectional study of 74 children. The data show that children acquiring Thai overgeneralize the causative alternation syntactically and semantically. Semantic overgeneralization continues longer than syntactic overgeneralization. The data indicate that syntactic overgeneralization is due to the children's focus on the result rather than the cause of an event early in their language development. The children use a verb in various sentence frames available to them before the argument structure of the verb is acquired. Semantic overgeneralization is due to the incomplete acquisition of verb meaning, particularly the selectional restrictions, as well as an incomplete understanding of the characteristics of objects in the world. Limiting the range of uses of verbs requires fixing the characteristics of objects in the real world that define the selectional restrictions for the verbs. The data also indicate that unlearning syntactic overgeneralization involves the meaning of a verb. Although verbs belong to the linguistic domain, deciding which verb to use in a particular event requires reference to real world through cognition. A first language acquisition theory must address the relation between language and cognition. The relation can be captured by viewing language users as both language users and cognizers who move back and forth between the linguistic world and the cognitive world. Establishing the conventional meaning of a verb and extending the conventional meaning to novel events is at the heart of our linguistic competence.