The aim of the present study is to investigate the relationship between language comprehension and language production in Swedish children. This was done longitudinally with 10 children with specific language impairment (SLI), aged 4;0 to 6;3 at Time I, and 10 children with unimpaired language development, aged 3;1 to 3;7 at Time I. The target structure was subordination, more precisely relative clauses. The children's comprehension was tested with picture pointing, act-out and oral response tests. Their production was tested with elicited imitation and sentence completion tests. Data were collected twice, with an interval of six months. The results from the unimpaired children at Time I showed a difference between comprehension and production. At Time II these children scored higher on production than on comprehension. The children with SLI scored significantly higher on comprehension than on production at Time I. In half of the SLI group there was a clear development between the two data collection sessions, diminishing the dissociation. On neither testing did the children with SLI differ significantly from the unimpaired children in comprehension. At both testings, however, the children with SLI had significantly more responses where they did not insert the complementizer in relative clauses. The results indicate that the relationship between comprehension and production is different at different stages in development. They also show that structures involving dependency relations are particularly difficult to produce for children with SLI.

The deaf teenagers with CI in the study seem to be equally collaborative and responsible conversational partners as the hearing teenagers. The interpretation is that certain conditions in this study facilitate their participation in conversation. Such conditions might be a calm environment, a task that is structured and without time limits and that the partner is well known to the teenager with CI.

Complex working memory seems to play a significant role in vocabulary acquisition in primary school age children. The interpretation is that the results support theories suggesting a weakened influence of phonological short-term memory on novel word learning in school age children.

Spontaneous speech samples from 10 Swedish children were collected and analyzed grammatically. The subjects consisted of 5 children with SLI and 5 MLU matched controls with normal grammatical development. The children with SLI differed significantly from the controls in their more restricted usage of word order patterns and in number of grammatical errors. As in studies on English-speaking children with SLI, the Swedish children with SLI had a large number of omissions of grammatical morphemes. Verb-related errors were more common than noun-related errors. Contrary to reports on children with SLI acquiring other languages, however, word order errors were also very common in the Swedish children with SLI. A restricted usage of word order patterns in combination with errors of word order indicates that not only morphological deficits but also syntactic difficulties can be found in children with SLI relative to MLU controls, depending on the target language. The findings show the importance of cross-linguistic comparisons of children with SLI.

Children with specific language impairment (SLI) are often described as having great difficulty with grammatical morphology, but most studies have focused only on these children's use of verb morphology. In this study, we examined the use of noun phrase (NP) morphology by preschool-age children with SLI who are acquiring Swedish. Relative to typically developing same-age peers and younger peers matched according to mean length of utterance, the children with SLI had greater difficulty in the use of genitive inflections, indefinite articles, and article + adjective + noun constructions. Their difficulties were evidenced in omissions as well as substitutions. Furthermore, article omissions were more frequent in NPs containing an adjective and a noun than in NPs with only a noun. These findings indicate that in languages such as Swedish, NP morphology as well as verb morphology can be quite problematic for children with SLI. Factors that might have contributed to these children's difficulties are the lack of transparency of the gender of Swedish nouns, the morphological complexity of NPs containing adjectives in Swedish, the weak syllable status of articles, and the consonantal nature of some of the inflections.