The modal verb necesitar and auxiliarity

Verbal periphrases in Spanish continue to pose difficulties in terms of their characterization and delimitation, due to the lack of reliable criteria that would allow to establish the defining features of auxiliary verbs. In this work we focus on the verb necesitar ‘need’, whose behavior in some infinitive constructions has led grammarians to treat it as semiauxiliary. With the aim of delving into the properties of this verb, we outline, first of all, the intrinsically modal meanings that it has as a lexical unit, and we then show that its function as an auxiliary shows up in contexts where the verb stops predicating a need of the subject to indicate the necessary occurrence of an event. Between one case and another, we identify ambiguous structures, in which the predicative load of necesitar is blurred as a result of the greater discursive prominence that the event expressed by the infinitive gains. KEYWORDS: discursive prominence; grammaticalization; modality; necesitar; verbal periphrase