The present study was designed to evaluate the linguistic capacities of retarded adolescents. Four different settings of verbal interaction were suggested to seventeen retarded adolescents. The conversations of each dyad were recorded on audiotape and transcribed word for word, then analysed according to eighteen indices. The analyses focused on the differences between situations by measuring the indices as well as the relationships between the indices. The results indicate that although the discourse of retarded adolescents is repetitive, it is almost always informative and varies according to the status of the interlocutor. Moreover, regarding its developmental aspect, age appears to be a significant factor in the use of communicative strategies; such findings may have pedagogical applications.