Researcher Roger Brown studied telegraphic speech in children by comparing?

Researcher Roger Brown studied telegraphic speech in children by comparing the language development of typically developing children with that of children with specific language impairments. He found that typically developing children followed a general pattern of language development, while children with language impairments showed delays and differences in their acquisition of language milestones. This research helped to provide insights into the typical progression of language development and the characteristics of language impairments.