The syntax of gerunds and infinitives: Subjects, case and control

This dissertation unifies the treatment of certain non-finite agreement, tense and control.; First, it presents a minimalist analysis of clausal gerunds in English-V- ing constructions with a PRO or a lexical NP subject marked with accusative or nominative Case. It is argued that sentential gerunds project at least a Verb Phrase, but vary in terms of phi-features and other functional projections, up to a Tense Phrase. They contrast with respect to overt and null subject licensing, tense and aspectual properties.; Second, it analyzes gerunds without overt subjects and gerunds as complements of perception verbs. It shows that tense and event binding do not entirely correlate with the contrast between control and raising/exceptional case marking (ECM), against null Case approaches to control.; Third, it accounts for the distinctions between inflected and non-inflected infinitives in Portuguese by analyzing obligatory control as the result of NP-movement.; Fourth, it accounts for changes in the history of Portuguese infinitives by adopting a theory of acquisition and change. It is shown that the loss of agreement morphology in inflected infinitives in Brazilian Portuguese has only partial syntactic effects, which follow from an NP-movement approach to control and from a theory that relies on the need for children to find local triggers to acquire their grammars.; It also evaluates the two major competing approaches for the rise of inflected infinitives in Old Portuguese, providing arguments from a cue-based theory of acquisition that this innovation is not the result of an analogy with finite forms.; Finally, it connects the loss of Brazilian Portuguese inflected infinitives to the widespread loss of agreement morphology and to a larger set of changes, including loss of verb-subject inversion and shifts in clitic placement. It is argued that these changes are connected with the weakening or loss of a single functional projection in the left periphery of the clause. These changes accelerate in the mid-19th century and are completed by the early 20th century, supporting an approach that links a series of catastrophic changes through a single structural change.