Introduction to Lexical constraints in grammar: Minority verb classes and restricted alternations

This is an introduction to the Special Issue Lexical constraints in grammar: Minority verb classes and restricted alternations. In many languages, grammatical relations are subject to lexical constraints. These constraints can be manifested in different morphosyntactic domains, for instance, through deviation from canonical case frames or different argument indexation patterns. Other constructions that have been studied through this lens are voice and valency constructions and some clause-combining constructions. The types of oppositions established by lexical constraints vary: some absolute restrictions entail the obligatory presence or absence of a grammatical marker, while others entail the ability of a lexical item to alternate. In the latter instance, differences in the statistical preferences for one construction over another may be observed. In some cases, verb classes can be easily identified based on a common semantic feature; however, various other factors can also lead to the formation of minority verb classes and restrictions on alternations. This article introduces a collection of four articles investigating lexical constraints in a variety of morphosyntactic domains, adopting different perspectives and methodologies. It sets out a framework for considering different opposition types formed by the differing behaviour of different verb classes and outlines a number of different factors that motivate the formation of verb classes. This introductory article shows that lexical constraints provide fertile ground for typologists adopting a token-based approach seeking to compare languages at ever-greater levels of specification.