Purpose: Hungarian is a null-subject language with both agglutinating and fusional elements in its verb inflection system, and agreement between the verb and object as well as between the verb and subject. These characteristics make this language a good test case for alternative accounts of the grammatical deficits of children with language impairment (LI).
Method: Twenty-five children with LI and 25 younger children serving as vocabulary controls (VC) repeated sentences whose verb inflections were masked by a cough. The verb inflections marked distinctions according to tense, person, number, and definiteness of the object.
Results: The children with LI were significantly less accurate than the VC children but generally showed the same performance profile across the inflection types. For both groups of children, the frequency of occurrence of the inflection in the language was a significant predictor of accuracy level. The two groups of children were also similar in their pattern of errors. Inflections produced in place of the correct inflection usually differed from the correct form on a single dimension (e.g., tense or definiteness), though no single dimension was consistently problematic.
Conclusions: Accounts that assume problems specific to agreement do not provide an explanation for the observed pattern of findings. The findings are generally compatible with accounts that assume processing limitations in children with LI, such as the morphological richness account. One nonmorphosyntactic factor (the retention of sequences of sounds) appeared to be functionally related to inflection accuracy and may prove to be important in a language with numerous inflections such as Hungarian.