The present study examined 2 year-old Hindi-speaking children's productivity with transitive and intransitive constructions using concurrent measures of experimental and naturalistic verb use. Productivity is a child's ability to use a new verb in a construction in which she has never before heard it.

In the experimental study seventeen 2.5, and sixteen, 3 year-old children were taught 6 familiar and 4 novel verbs for two types of transitive events. One in which the agent directly brought about a change in the object and one in which the agent used an instrument to bring about the change. Each child learnt half the familiar and novel verbs in the transitive construction (e.g., ladka paani ko gam-aa raha hae- 'the boy is gain the water') and half the verbs in the intransitive construction (paani gam gaya - the water is gam-ed'). Results show that most 2.5 year old Hindi-speaking children are productive in the use of constructions with novel verbs in both types of events. All children performed better with familiar verbs and 2.5 year-olds were better at producing an unmodeled transitive construction than an intransitive construction.

Studies two and three examined the relation of children's novel verb use with their own and their caregivers' verb use in play contexts. Three children who were productive and three who were not productive in the experimental task and their caregivers were recorded in naturalistic play contexts for an hour each week for four weeks. Findings show a strong link between children's productivity with novel verbs and their own and their caregivers' use of transitive and intransitive constructions diversely with a number of verbs and argument frames in naturalistic contexts.

These results suggest that languages with explicit markings for agent-patient relations facilitate an earlier onset of productivity than word-order languages like English. Additionally, the number of verb types used in familiar constructions helps children understand the meaning of the construction. Therefore, studying concurrent measures of novel and familiar verb use is useful in developing a more accurate account of the processes by which children extract structure and meaning to build up a more complex grammar.