Most of the developments in the part-whole relationship in French are generally based on the predicate être une partie de 'be a part of ' or on the auxiliary avoir 'have', and their comparison. We will look into a complex French predicate which, unlike the two previous ones, has not been the subject of a precise definition despite its numerous occurrences: faire partie de. As is the case of the two previous situations, this predicate establishes a relationship between a part and a whole, but with some interesting specificities. In order to describe them, we will focus on a comparison between two constructions: NP0 faire partie de NP1 and NP0 être une partie de NP1. We will show the existence of a double constraint: the internal plurality of NP1 and the dependent character of NP0 in relation to NP1. We will show that it results in coercion effects as well as variations in profiling. These observations will allow us to turn to idiomatic expressions, such as [NP faire partie des {meubles/des murs/du paysage/du décor}] 'NP is part of the furniture/the walls/ landscape/décor' or [NP être la partie {visible/invisible} de l'iceberg.] 'NP is the {visible/hidden} part of the iceberg'. We will show that these follow from the semantic properties of the two structures.
