This research investigates the interface Syntax/Prosody conditions in structures containing Nominal Gapping (EN from Portuguese Elisão Nominal). The literature about EN reports restrictions about nominal gapping followed by a prepositional phrase. Our research investigates this restriction based on data from Brazilian Portuguese. Our central hypothesis is that the occurrence of nominal gapping in the mentioned context depends on the interface conditions between syntax and phonology (i.e. mapping of syntactic domains in prosodic domains). In order to verify this hypothesis, four experiments were conducted with methodology of experimental carachter. The first – acceptability test with use of scale – verifies the occurrence of the phenomenon in Brazilian Portuguese. Other experiments, based on oral reproduction test, sought to verify in which conditions the sentences in the examined context considered ungrammatical in European Portuguese are accepted by native speakers of Brazilian Portuguese. The results indicated that the licensing of these sentences is associated to the process of prosodic adjustment as result of the application of phonological processes (as sandhi, for instance) and the manipulation of prosodic features (such as duration), in which the definite article, because of its fragile prosodic status, tends to be elided. Our research evidences, therefore, some repair strategies employed by the speakers to satisfy the interface conditions between Syntax and Phonology. Thus, this study contributes for a better theoretical understanding of Grammar, specifying interface conditions and the relations between Syntax and other Grammar components.