A gradient typology of gerund clauses: revisiting the internal and external syntax of Portuguese gerund clauses

Focusing mostly on European Portuguese, this paper proposes that the internal syntax of Portuguese gerund clauses and the gradience in their degree of defectiveness may be explained by an interplay between their external syntax (locus of merge), agreement relations between embedded Tense and matrix Tense and the presence/absence of an intervening head. We first revisit the distinction between peripheral adverbial gerund clauses and central adverbial gerund clauses and show that their internal syntax correlates with their external syntax: central adverbial gerund clauses are merged in lower positions and appear to be more defective. We derive their defectiveness from the agree relation established between embedded T and matrix T. We then consider predicative gerund clauses and show that they are even more defective and restricted in their aspectual value, lacking a T head. Finally, we consider predicative gerund clauses introduced by como ‘as’ and show that, although they are merged in a low position, they are less defective than central adverbial gerund clauses. We attribute this mismatch between the internal and external syntax of this specific type of gerund clause to the presence of the Predicate head como, which intervenes between matrix T and embedded T and blocks the agreement relation.