Two hypotheses regarding the distribution of emergent tense-aspect morphology in SLA have been proposed: the aspect hypothesis, which claims the distribution of interlanguage verbal morphology is determined by lexical aspectual class, and the discourse hypothesis, which claims it is determined by narrative structure. Recent studies have tested and supported both hypotheses individually. This study expands the investigation to include an analysis of both narrative structure and lexical aspectual class in a single corpus comprising 74 narratives (37 oral and written pairs) produced by adult learners of English as a second language at various proficiency levels. The results suggest that both hypotheses are necessary to account for the distribution of verbal morphology in interlanguage.