English infinitival relative clauses exhibit variable force deontic modality, with the restriction that whereas a weak necessity ( should -like) reading is always available, a possibility ( can/could -like) reading is available only under weak quantifiers. I propose: weak necessity modals have a degree semantics, whereby combination with a silent positive morpheme yields weak necessity; existential closure of the degree variable yields possibility; and existential closure is available only under weak quantifiers because only they are interpreted within VP. The account supports the view that modality is scalar, that deontic possibility and (weak) necessity occupy the same scale, and that existential closure is structurally constrained.

A bound pronoun in the subject position of a finite embedded clause renders the clause boundary relatively transparent to relations ordinarily confined to monoclausal, control, and raising configurations. For example, too / enough -movement structures involving a finite clause boundary are degraded in sentences like * This book is too long [for John to claim [that Bill read ___ in a day]] but improved when the finite clause has a bound pronominal subject as in ? This book is too long [for John 1 to claim [that he 1 read ___ in a day]] . This bound pronoun effect holds across a wide range of phenomena including too / enough -movement, tough -movement, gapping, comparative deletion, antecedent-contained deletion, quantifier scope interaction, multiple questions, pseudogapping, reciprocal binding, and multiple sluicing; we confirm the effect via a sentence acceptability experiment targeting some of these phenomena. Our account has two crucial ingredients: (a) bound pronouns optionally enter the derivation with unvalued ϕ-features and (b) phases are defined in part by convergence, so that under certain conditions, unvalued features void the phasal status of CP and extend the locality domain for syntactic operations.