The goal of this paper is to test the hypothesis according which a young child (3 y.o.) has got a form of linguistic awareness. This is in the social relationships that adults (for example) act on the child's linguistic representations to change them. Thus, adult's conducts are very important in the categorisation process which will allow the child to construct his representations system with the better manner to be the nearest adult's representations system. This experience with only one child is a preliminary case study, a French case study, before applying to a more important population. Thus, with a diachronic observation during several months, it will be possible to note the different behaviours of the child, about the pronunciation of 'tractor'.