Default Morphology in Second Language Spanish
Morphological variability is a persistent and systematic phenomenon whose source is the subject of current debate in second language theory. In this paper, I argue that variability is not equivalent to missing inflection, as defaults are typically incorrectly inflected for tense and person-number agreement. Data from the spontaneous production of 11 advanced and intermediate speakers of Spanish show that nonfinite defaults are rare, contrary to the expectations of the Missing Surface Inflection Hypothesis. Furthermore, default morphology is systematic: 3<sup>rd</sup> person acts as a default in non-3<sup>rd</sup> contexts, present-tense in past contexts, and singular in plural contexts—the reverse of these does not occur. I propose an underspecification-based theory, coupled with independently-derived markedness criteria, that predicts the morphemes that are adopted as defaults.