Production of grammatical number in specific language impairment: An elicitation experiment on Finnish.

A wug type of plural production task with Finnish-speaking 10- to 11-year-old normals and 10-year-old SLI children shows that formal transparency of affixation and the lexicality (real words vs pseudowords) of the stimuli affect the performance of both groups. Not unexpectedly, nontransparent pseudowords receive drastically low correctness rates among the SLI speakers. The failures of the SLI group corroborate the claim that they have not internalized the productive inflectional morphology involved in plural formation to the extent that their normal, age-matched peers have. Copyright 1999 Academic Press.