The syntactic and semantic features of two-year-olds' verb vocabularies: a comparison of typically developing children and late talkers.

The Language Development Survey was not originally designed to analyse verb syntax or semantics. The study did not measure children's receptive vocabulary, so it cannot say what children understood but did not produce. The checklist does not show how often each child used each verb in daily life or in what sentence contexts. The sample had limited demographic information beyond age and sex. The children were all English learners, so the syntax findings may not apply to other languages. Verb classifications came from linguistic resources and tests, not from each child's actual exposure. Input frequency was estimated from a parent speech corpus, not from the children's own caregivers. The analysis did not include information about whether children later received a diagnosis, so it cannot show what predicts later disorder.

The supplied publication types list NIH extramural research support. No author conflict-of-interest statement appears in the supplied text.

Do not read the manner-verb difference as proof that late talkers have a specific verb-learning disorder or that they need a different verb intervention. It is based on parent-reported verbs at one age, with no diagnosis, no follow-up, and no evidence about how children learned the verbs; it may reflect small vocabulary size.