Production of tense morphology by Afrikaans-speaking children with and without specific language impairment

To establish whether the predictions of the extended optional infinitive (EOI) hypothesis (Rice, Wexler, & Cleave, 1995) hold for the language of Afrikaans-speaking children with specific language impairment (SLI) and whether tense marking is a possible clinical marker of SLI in Afrikaans.

Production of tense morphology was examined in 3 groups of Afrikaans-speaking children-15 with SLI who were 6 years old, 15 typically developing (TD) 4-year-olds matched on mean length of utterance, and 15 TD 6-year-olds-using both elicited and spontaneously produced verb forms.

On the sentence completion task, children with SLI fared on par with 4-year-olds and worse than age-matched peers. However, in terms of spontaneous production of morphemes pertaining to tense, children with SLI fared worse than both TD groups. Furthermore, children with SLI mostly made the same types of errors as 4-year-olds, although some errors were unique to the SLI group. Most errors entailed omissions, of modal and temporal auxiliaries as well as of copula be.

The errors offer support for the EOI hypothesis. Tense marking has the potential to be a clinical marker of SLI in Afrikaans, but further research with larger groups of Afrikaans-speaking children, including children of other ages, is needed to confirm this.