The Aspect Hypothesis suggests children’s early verb production choices to use perfect or progressive verb form (-ed vs. -ing respectively) can depend on event semantics (Shirai & Andersen 1995). Children tend to use perfective constructions with verbs denoting completion, while present constructions mostly occur with verbs denoting ongoing actions. Li and Shirai (2000) suggest that children may stray from this pattern as caregiver input changes throughout development.

However, these changes are underexplored, and previous findings supporting the Aspect Hypothesis emerge from limited corpora. Our study used NLP on all English corpora in the CHILDES corpus to extract the main verbs from the utterances of children and caregivers. We confirmed children and caregivers’ general adherence to the predicted pattern. We also found preliminary support for caregivers’ shifting in their inflection of multiple verb types. Our findings support the Aspect Hypothesis and provide insight into how children come to broaden their inflections.