The Words-and-Rules theory is a relatively new development in the area of
morphological productivity. This theory claims that irregulars are stored
in the mental lexicon, while regulars are formed by a rule that attaches an
affix to items that do not have a stored inflected form available.
The major contribution of this thesis is to test the rule component of the
Words-and-Rules theory on the basis of Dutch pluralisation, including newly
collected acquisition data. Dutch is a language that seemingly has two
plural affixes acting as defaults, -s and –en. Investigating acquisition is
motivated by the claim that the theory is universal, which suggests that
children acquiring Dutch should look for a single default, despite the
input they receive. Experimentally obtained data reported on in this thesis
(including data from children between just under three and six years of age
and adult controls) force a reconsideration of the rule component of the
theory. Speakers of Dutch, adults and first language learners, have only
one true default, but the rival affix is still regular. This finding leads
to a modification of the theory towards a constraint-based model of
Words-and-Constraints, in which crucially the possibility exists to
differentiate defaults from regulars.
The Acquisition of the Dutch Plural is of interest to researchers in the
fields of phonology, psycholinguistics, language acquisition and morphology.