This study ultimately aims at identifying the rhetorical question at a formal level, even taking into account the fact that this may seem unthinkable to most grammarians and linguists. Nevertheless, the analysis of the different modalities of questions, their form and the relationship they have with their semantic-pragmatic field, can lead to the identification of some formal characteristics closer to the category of rhetorical question. In the course of this work, concrete interrogative structures will be analysed in the context in which they were uttered. The problem that arises at this point is precisely that formal analysis is mixed with discourse analysis, since questions often cannot be correctly interpreted without taking into account the answers that are given to them afterwards. The rhetorical question is an ideal research subject to measure the importance of the interface of the various branches of linguistics - morphology, syntax, semantics, pragmatics and even semiology, since the written question is accompanied by a sign.