Negative evidence and grammatical morpheme acquisition.

Children's use of negative evidence in language acquisition was investigated. Recent research has demonstrated that parents differentially correct children's ungrammatical sentences compared with grammatical sentences through recasts (i.e., negative evidence). This study investigated children's imitations of new gramamtical morphemes contained in corrective recasts. These imitations were compared with imitations of grammatical morphemes contained in positive evidence provided by discourse type such as topic continuations. One hr of conversation in twelve 23-month-old children and their mothers was examined