Özet:
Morphological systems that possess irregular suffixation provide us important cues with respect to how words are processed and represented in the mind. This study attempts to find out how adult speakers of Turkish process and represent the aorist, an irregular pattern proven to be extremely challenging in acquisition, as it takes the form of -r for vowel-ending verbs (uyu-r ‘sleeps’), -Ar for most monosyllabic verbs (çal-ar ‘plays’), and -Ir for multisyllabic verbs (çalış-ır ‘works’) and 13 monosyllabic sonorant-ending verbs (al-ır ‘takes’). In this study we have tested 90 native speakers with respect to their production of the aorist with 168 monosyllabic, sonorant-ending nonce roots (vel-, rur-, etc.). Participants were auditorily presented with sentences that contained nonce roots and instructed to orally conjugate the nonce root in a subsequent carrier sentence such as in Ali biraz önce veldi. Ali yazın her gece vel____. 'Ali velled a short while ago. Every summer night, Ali vel___.' Our results have shown that adult speakers of Turkish have opted for the use of -Ar with a rate of 86% (i.e., vel-er preferred over vel-ir by the overwhelming majority). To uncover the role of similarity in the use of –Ir, we have explored various similarity measures and have found that -Ir use appears to be correlated with the type frequency of existing irregulars sharing the same first consonant C_ _, the same first vowel _V_ and the consonantal template C_C. Rhyme, however did not appear to be a salient cue that language users rely on.