In recent years, attempts to simplify the grammatical mechanisms used in syntax have led to proposals to reduce the relationships between elements in a sentence to relations between heads and complements, doing away with free adjunction. For the analysis of modifying relations one consequence has been the rise of analyses that use the properties of selecting heads to stipulate unexpected syntactic behaviour, such as the use of light verbs to derive transparency in complex verb constructions.

This thesis shows that such accounts are empirically inadequate and argues that the relationship between heads and adjuncts provides a more empirically-satisfactory model of modifying relations, such as complex verb constructions, than one restricted to the selection relation between heads and complements in the syntax. In support of the adjunct relation, I show how a modular approach to adjuncts in which the position of adjunction is licensed in the semantics and long-distance dependencies are licensed in the syntax can provide a more unified account of subextraction from two separate types of island configurations, viz. asymmetric subextraction from coordination and subextraction from participial adjuncts, either than analyses involving complementation in the syntax (Borgonovo and Neeleman, 2000; Fabregas and Jiménez-Fernández, 2016; Wiklund, 2007), or hybrid analyses mixing processing filters with syntactic licensing of long-distance dependencies (Truswell, 2009, 2011).

The first part of the thesis shows that Chomsky’s (2000; 2001) phase theory gives rise to blackholes in the specifier positions of phases from which movement cannot take place. I provide a theoretical account in terms of feature-licensing, where blackholes are formed by the impossibility of licensing at least one unlicensed feature on a phase head, and show how this account derives the distinction between canonical adjuncts from which subextraction is not permitted and subextraction from single event constructions in which subextraction is permitted. The section speculatively concludes with a demonstration of how blackholes might provide a unified analysis of islandhood in general.

The second part of the thesis concentrates on the empirical phenomenon of subextraction from coordination and participial adjuncts. I report the results of a series of judgement experiments run in parallel across two sets of constructions, coordination and participial adjuncts, in three languages, English, German and Norwegian. The aim was to test whether acceptability of subextraction from within coordination and participial adjuncts varied depending on the aspectual or grammatical type of matrix predicate. The results show that acceptability of subextraction does depend on the type of matrix predicate. The crucial factor is intransitivity, partially confirming the bias towards unaccusatives in subextraction from participial adjuncts observed informally in Borgonovo and Neeleman (2000); Fabregas and Jiménez-Fernández (2016); Truswell (2011) whilst providing evidence against theoretical accounts that rely primarily on unaccusativity (Borgonovo and Neeleman, 2000; Fabregas and Jiménez-Fernández, 2016), primarily on aspectual distinctions (Truswell, 2007b) or primarily on agentivity (Truswell, 2009, 2011). Interestingly, the hierarchy in acceptability between the four types of matrix predicates stays constant across all three languages, despite both pseudocoordination and subextraction from within participials being ungrammatical in German.