Mistakes weren't made: Three-year-olds' comprehension of novel-verb passives provides evidence for early abstract syntax.

By about age three, English-learning children begin to understand passive sentences with familiar verbs. We probed the nature of children's linguistic representations by asking whether 3-year-olds promptly extend their emerging knowledge of the passive structure to novel verbs. In three preferential-looking experiments, 3-year-olds (N = 124) interpreted novel verbs presented in short passives (Experiment 1, "She's getting snedded!") as transitive verbs, referring to causal-action rather than solo-action events, and used word-order in full passives, (Experiments 2 and 3, e.g., "She's getting snedded by the boy!"), to select a target event in which the subject was the patient, not the agent of action. Comprehension accuracy in Experiments 1 and 2 varied with vocabulary, but this vocabulary effect disappeared when children were given more time and more repetitions of the test sentences (Experiment 3). These findings support early-abstraction accounts of acquisition: 3-year-olds represent passive syntax in abstract terms, permitting extension to novel verbs. This, in turn, allows them to use passive sentences to identify the grammatical subcategory and meaning of an unknown verb.