Interpretation of imperfective past tense in Spanish: how do child and adult language varieties differ?

Some studies on the L1 acquisition of aspect in various child languages have discovered that imperfective aspect is acquired later than perfective aspect, whereas others find early adultlike performance. A variety of explanations has been advanced, particularly problems (i) with the semantics of imperfective aspect in combination with telic predicates, (ii) inferring the intended temporal antecedent in a discourse, and (iii) reasoning about an agent’s intentions to complete the event when observing a situation of an event in progress. The current study aimed to disentangle which of the purported explanations can best explain the acquisition patterns. Twenty-three Spanish monolingual children (mean age 5;11) and 17 adults were presented with telic sentences with one of two aspectual tenses in Spanish (pretérito indefinido and pretérito imperfecto). Using a picture-selection task and presenting the sentences either in a narrative setting or in a non-narrative setting, participants were prompted to choose between complete, ongoing, and incomplete situations. In the non-narrative setting children’s interpretation of imperfecto was adult-like, but in the narrative setting it was not. The target-like interpretation in the non-narrative setting reveals that the semantics of imperfecto in telic-imperfective sentences has been acquired (contra explanation i). Furthermore, Spanish fiveyear-olds did not depend on cues for agent intentionality when interpreting the imperfecto (contra explanation iii). The discrepancy between narrative and non-narrative setting suggests the challenge lies in discourse integration (supporting explanation ii).