This work aims at modelising the use of the suprasegmental system and its relation with the enunciative structure in young children in a dialogue situation with a competent speaker. The role of the intonative and temporal parameters during the grammaticalisation period, which takes place between 2 and 3.5 years of age is investigated in this paper. Results show that children who use intonation precociously for communicative purposes, also use it in a specific way related to their ability to detach themselves from the context. Three chronological periods emerge. As time goes by the complexification of the grammatical structures generates a functional redistribution of prosody.