Near-synonymy in morphological structures

This article examines the concept of defectivity in the verbal system of Spanish, Portuguese and Catalan. Building on previous studies on defective verbs in Spanish and Portuguese I investigate why there are no such defective verbs in Catalan. I conclude that the structure of the verbal paradigm in Catalan non-first conjugation verbs is radically different from that of the other languages; Catalan verbs constitute paradigms which correspond to regular patterns of inflection whereas Spanish and Portuguese display non-predictable types of root allomorphy which require all non-first conjugation verbs to have a memorised form for the rhizotonic forms of the verb. Theoretically, this type of defectivity poses problems for models of inflectional morphology and suggests that the patterns of frequent verbs can become general rules for all verbs of a particular conjugation.