Les interrogatives compléments en français

French interrogative clauses, whether root or embedded, rely on more syntactic combinaisons than has usually been assumed. In addition to the filler and head phrase (à qui Paul a parlé, ‘to whom Paul spoke’) , and the head and complement phrase (si Paul a parlé, ‘if Paul spoke’), we need the head and adjunct phrase for the adverbe pourquoi (why), and one use of comment (‘how come’) as well as the pronoun quoi. Interestingly, compelemnt interrogative clauses raise the question of the very definition of interrogatives: their contenis not unifrm, since they denote either a question or a proposition whihc is the answer to a question. After a general presentation of the data, and of the classification of verbs taking an interrogative complement, we propose an analysis in the framework of HPSG, relying more particularly on Ginzburg and Sag (2000), whose general framework we adopt as well as the analysis of the probelmatic verbs in terms of interpolation (or lexical coercion).