ABSTRACT
This chapter summarizes key findings of the book and suggests additional avenues for ongoing research. The structures investigated here provide insights into some of the most fascinating aspects of human linguistic forms, including displacement, long-distance dependencies, ellipsis, and the prominent role of the clausal periphery. An emergent finding addressed here is that certain marginal structures or strings with particular surface characteristics may have multiple possible underlying forms and/or multiple possible derivations. At first, this might not seem terribly remarkable in that strings that are structurally ambiguous have more than one derivation or parse, each associated with a distinct interpretation. But in the type of strings we explore here in lesser-studied languages, such as parasitic gaps, ellipses, and long-distance dependencies, we investigate the question of multiple parses of a particular variety: that (a) have no perceptible interpretive distinction between them and (b) have often quite complex derivations, costly to the grammar in some measurable way. In other words, it is not the formal property of the grammar as ambiguous which concerns us, but instead a clear understanding of what constrains syntax, on the one hand, and what must be minimally available to the grammar of all human languages, on the other.
