Abstract
This paper presents a short-term longitudinal study of specific language impairment (SLI) in school children and tries to give a detailed linguistic and non-linguistic description of the phenomenon. Two groups of elementary school children, grade 1 to 4, age 7 to 10, were tested. The first group consisted of children with SLI (n = 61) and the control group consisted of children with no language difficulties (n = 61). There follows a detailed presentation of two language variables (plural/dual formation and detection and correction of incorrect inflections). The results obtained are discussed. The conclusion which could be drawn is that children with SLI show more problems in knowledge of language and its usage, though they are not characterized by any kind of general language deficiency.