Irregular past tense formation in English interlanguage

In 1983, when I attended my first linguistics course, taught by one Professor Rüdiger Zimmermann, Joan Bybee and Carol Moder published an article on „Morphological classes as natural categories“ in Language. In this article they argued that prototype theory can be applied to morphological classes, in particular ablaut classes in English verb morphology. Their experimental results indicated that native speakers of English do not only use regular inflexion, i.e. -ed, to construct past tense forms from given nonce verbs but that, to a certain extent, they also generalize certain ablaut patterns. The probability of the respondents choosing ablaut instead of the more expectable regular past tense suffix crucially depended on the similarity of the nonce verb with a phonologically defined prototype. The present article reports the results of a study inspired by the Bybee and Moder paper which was designed and carried out by two second-year students and myself in my 1996/97 morphology proseminar.1 The aim of the study was to test whether irregular past tense formation in advanced English interlanguage shows the same patterning as observed with Bybee and Moder's native speakers. More specifically, we tried to answer the question whether advanced learners construct an ablaut-triggering prototype and if so, whether it is the same as with native speakers of English.