Categories, features and values in the definition of a word class

Abstract

The model suggested by Pullum (1994) in order to define the word classes (i.e. the traditional ‘parts-of-speech’ [PoS]) seems to be the most adequate among the many models that have been proposed. A word class is a set of linguistic objects having common traits which, on their turn, are implemented by particular values  (see fn. 1  for the graphic devices to distinguish between ‘categories’, ‘features’, and ‘values’). Thus, verbs may share with nouns and pronouns features such as gender and number. For instance, a possible implementation of the trait – technically called ‘feature’ – mood can be subjunctive while a possible implementation of the feature gender is feminine. Some values may be shared by different categories or features – though not all at the same time. Word classes are not water-proof boxes and lexemes may leak from a class to another one. For instance, the -ing forms show different functions according to different contexts (for a ‘construction grammar’ approach see Croft, 2007: 421, who speaks of  «overlapping categories of formatives which represent their diverse distributional behaviour»): These cars want washing_VBcarefully versus These cars want careful washing_N. Category shifts (i.e. transcategorizations) are caused by the morphosyntactic constructs they appear in. Engl. bar is properly the imperative of the verb to bar “to prevent”, but in a sentence like Everyone is leaving bar Ernst, it has prepositional function.