Existential and locative constructions form an interesting cluster of copular structures in Romance. They are clearly related, and yet there are theoretical reasons to keep them apart. In-depth analysis of the Romance languages lends empirical support to their differentiation. In semantic terms, existentials express propositions about existence or presence in an implicit contextual domain, whereas locatives express propositions about the location of an entity. In terms of information structure, existentials are typically all new or broad focus constructions. Locatives are normally characterized by focus on the location, although this can also be a presupposed topic.
Romance existentials are formed with a copula and a postcopular phrase (the pivot). A wide range of variation is found in copula selection, copula-pivot agreement, expletive subjects, the presence and function of an etymologically locative precopular proform, and, finally, the categorial status of the pivot, which is normally a noun phrase, but can also be an adjective (Calabrian, Sicilian). As for Romance locatives, a distinction must be drawn between, on the one hand, a construction with canonical SV order and S-V agreement and, on the other hand, another construction, with VS order and, in some languages, lack of V-S agreement. This latter structure has been named inverse locative.
Both existentials and locatives have a nonverbal predicate: the locative phrase in locatives and the postcopular noun or adjectival phrase in existentials. In locatives the predicate selects a thematic argument (i.e., an argument endowed with a thematic role), which serves as the syntactic subject, exception being made for inverse locatives in some languages. Contrastingly, in existentials, there is no thematic argument. In some languages the copula turns to the pivot for agreement, as this is the only overt noun phrase endowed with person and number features (Italian, Friulian, Romanian, etc.). In other languages this non-canonical agreement is not licensed (French, some Calabrian dialects, Brazilian Portuguese, etc.). In others still (Spanish, Sardinian, European Portuguese, Catalan, Gallo-Italian, etc.), it is only admitted with pivot classes that can be defined in terms of specificity. When the copula does not agree with the pivot, an expletive subject form may figure in precopular position. The cross-linguistic variation in copula-pivot agreement has been claimed to depend on language-specific constraints on subjecthood.
Highly specific pivots are only admitted in contextualized existentials, which express a proposition about the presence of an individual or an entity in a given and salient context. These existentials are found in all the Romance languages and would seem to defy the semantico-pragmatic constraints on the pivot that are widely known as Definiteness Effects.
Topicality and differential object marking