Purpose: The current study used an intervention design to test the hypothesis that parent input sentences with diverse lexical noun phrase (NP) subjects would accelerate growth in children's sentence diversity. Method: Child growth in third person sentence diversity was modeled from 21-30 months (n = 38) in conversational language samples obtained…

This book is the second to present the results on a study of how children's practice of speech, as shaped by family interaction, affects learning to talk. Participating in the study were 42 diverse families with young children. Each month for 2.5 years the interactions between 42 one- to two-year-olds and their parents were recorded as the…