[The role of prefabs in grammaticization, Part III. Historical change]
Studies of grammaticization often reveal skewed distributions of lexical items in grammaticizing constructions, suggesting the presence of prefabs using these constructions. We examine here the role of prefabs in the grammaticization of <i>can</i> in English and the progressive <i>estar</i> ‘be (located)’ + V-<i>ndo</i> (Gerund) in Spanish. The data suggest that prefabs play a role in advancing formal and semantic change. We argue that (1) prefabs are ahead of the general construction in unit-hood status in early stages and thus demote the independent lexical status of the emerging grams, and (2) in their association with semantic classes of which they are the most frequent member, prefabs promote the productivity of the general construction. The evidence shows that prefabs maintain associations with the related general construction.