Left dislocated subjects and the pro-drop parameter: A case study of Spanish☆

Abstract The typical assumption in a pro-drop language like Spanish is that covert as well as overt subjects occupy a preverbal position at Spell Out in which their case and agreement properties are satisfied. This paper presents evidence against such a claim. On the one hand, we show that pre-verbal overt subjects pattern with left dislocated DOs and IOs in a wide range of syntactic contexts: ellipsis, extraction of quantifiers and interpretation of preverbal quantifiers. In these same contexts, sentences with a silent subject differ from sentences with overt ones. We conclude that overt pre-verbal subjects are necessarily left dislocated. In order to account for the left dislocated nature of overt subjects, we propose to eliminate AgrS as a functional projection. Instead we take the idea that subject agreement should be considered a clitic (Taraldsen, 1992), and the relation between the agreement and subject to be one of clitic doubling. Evidence in favor of this claim comes from striking parallelisms between standard clitic doubling constructions and agreement-subject constructions. Specifically, both cases pattern similarly in relation to the determination of binding in certain cases of mismatches in person between the doubling DP and the clitic. Since we take agreement to be a clitic that absorbs theta role and case, movement of the doubling DP subject to a preverbal position cannot be driven by agreement or case reasons. Instead, movement of the subject to a pre-verbal position is driven by discourse considerations as is typical in left dislocations.