Keywords: Complex syntax, prosody, MLU, development of language
This study describes the development of syntax complexity in 100 preschoolers. It represents a comparison between the measure of the Mean Length of the Utterance and new qualitative index of complexity as the clause (or proposition) or presence of connectives. The novelty of this research was the use of the prosodic component to study complex syntax, considering intonation as link for the linguistic elements in the utterance. On the whole, the results point out that the number of clauses increases, starting from 2 years old an half and the MLU increases as well. Nevertheless, the syntactic links between clauses mostly mark the linguistic production of the 3 years and a half children. 4 years old children MLU does not show furter increase, but their linguistic production is characterized by the presence of single clauses performed inside a single prosodic contour. These clauses are joined together by syntactic elements (connectives) and grammatical elements (vertical structured such as verb-argument). These finding will be discussed in a functionalist perspective for the study of language development particulary for what concerns the constructivist hypothesis and the recent research in the field of intonation.