SUMMARY
In English, subject-verb agreement is deemed to be ‘local’ if the controller (i.e., the subject) and the target (i.e., the main verb) are adjacent, but ‘non-local’ if these items are separated by one or more terminal nodes. Previous research indicates that second language English learners whose first languages lack subject-verb agreement tend to supply inflection for this functional category less accurately in non-adjacent than adjacent contexts in spoken production. This asymmetry could be driven by either adjacency or locality, since, for subject-verb agreement at least, these two properties are aligned with each other. Phrase-internal agreement, by contrast, is local regardless of whether the controller (i.e., a determiner or quantifier) and the target (i.e., a noun) are adjacent or non-adjacent; hence, for this type of agreement, adjacency and locality are not aligned with each other. In the present study, we gave a sentence-construction task to 64 native speakers of Vietnamese, a language without inflection for number agreement. Suppliance of inflection was lower in non-adjacent than adjacent contexts phrase-internally, and therefore within the local domain itself. We concluded that what gave rise to the asymmetries in inflectional production in our study, and, by extension, also in previous research on subject-verb agreement, was not the distinction between local and non-local domains, but rather the one between adjacent and non-adjacent contexts for agreement. In so doing, we present a more parsimonious analysis of asymmetries in the spoken production of agreement inflection than the one currently available.