Discourse and the acquisition of eat.

English has several classes of transitive verbs which can optionally appear without an undergoer. Despite their similar syntactic subcategorization, there are at least three different semantic subclasses that allow undergoer omission. Information sources based on surface structure, for example, syntactic bootstrapping, cannot inform the child of the semantic representation of these verbs. The focus of this paper is the acquisition of a single English verb, eat. The transcripts of 40 children, who were audiotaped monthly from 1;0 to 3;0, showed that eat was the first member of this verb class to be acquired. Some 1276 eat sentences were analysed for the presence of overt undergoer arguments across levels of cumulative verb lexicon (CVL) size, and two discourse conditions: (1) UNDERGOER ACCESSIBLE and (2) OPEN (to undergoer omission). Results indicate that undergoer omission became associated with discourse conditions when CVL size rose above 75 types, at MLU approximately 2.4 and age approximately 2;3. This suggests that two-year-old children are sensitive to a relationship between undergoer omission and discourse context.