The omission of subject arguments in children with specific language impairment.

Ten children with specific language impairment (SLI) were compared to two groups of normally developing children for the production of grammatical subjects in sentences of varying length and argument structure complexity. The normal controls consisted of a group of younger children matched for mean length of utterance (MLU) and a group matched for chronological age. The participants were asked to produce sentences of varied argument structure complexity using a story completion task. The results indicated that both the children with SLI and the MLU controls omitted more subject arguments in the ditransitive sentences than in sentences with intransitive and ditransitive verbs. In addition, more children with SLI omitted subject arguments as linguistic complexity increased. This effect was not found for the normal age control children who never omitted subjects, regardless of increases in argument structure complexity. These results support the notion that grammatical errors in both children with SLI and their younger, normal counterparts may be due to problems with processing complex linguistic information rather than with limitations in linguistic knowledge.