Consequences of the comparative fallacy for the acquisition of grammatical aspect in Spanish

Abstract This paper tackles the usefulness of comparing L2 learners against native speakers in empirical SLA studies focusing on grammatical aspect. Adapting view that interlanguage grammars should be analysed their own right instead as a deficient form target, we show expressing perspectivity (fulfilled by aspect markers) methodologically complicates analyses Grammaticality Judgment Tasks studies. For Spanish past tenses, especially with items constructed allegedly ungrammatical natives behave heterogeneously. casts doubt question whether these data can used baseline which learners’ could compared. By analysing separately (not only comparison to controls), our findings among German suggest use forms depends essentially temporal markers related both L1 lacking and pedagogical input. Crucially, though does not match target (i.e., tenses do necessarily correlate aspectuality), systems are chaotic but follow well-defined rules.