Abstract
Low verb diversity and heavy reliance on a small set of high-frequency 'general all purpose (GAP)' verbs have been reported to characterize specific language impairment (SLI) in preschool children. However, discrepancies exist about the severity of this deficit, particularly in whether these children's verb diversity is commensurate with their MLU level and whether verb diversity is more severely affected than general lexical diversity. Conflicting findings have been reported regarding the use of GAP verbs. This relatively large ( n =100) study extended the investigation of lexical diversity and high-frequency verb use to school-age children with SLI and NL peers and examined a particular hypothesis concerning the role of high-frequency verbs in language development. No differences were found between groups in general lexical diversity or verb diversity in samples of a set number of tokens. The results did not suggest that verb diversity constitutes an area of specific deficit in spontaneous production for children with SLI. SLI and NL groups were indistinguishable in high-frequency verb use. Extensive use of high-frequency verbs by both groups indicates that their use is part of normal development. Results are reported that support the hypothesis that high-frequency verbs act as prototypes for major meaning categories, permitting semantic and syntactic simplification with minimal losses in information value.