“Ser” or “Estar” + Adjective in L2 Spanish: An Experimental Study on the Acquisition of the Spanish Copulas by Native Italian Learners

This thesis investigates how Italian-speaking learners of L2 Spanish internalise the distinction between the copulas ser and estar when paired with adjectives. An experimental study with 19 university-level participants employed a grammaticality judgment task involving 64 sentences containing SER/ESTAR + ADJECTIVE combinations, filler and benchmark sentences (with ESTAR + GERUND). The experiment was carried out using “Kahoot!”, allowing accuracy and reaction times to be recorded. Two research questions guided the empirical study: RQ 1 – Are L2 learners of Spanish truly able to acquire and generalise this rule across any context or is their knowledge still predominantly tied to statistical learning and the memorisation of specific chunks taught in the classroom? RQ 2 – Are learners who demonstrate the ability to recognise verbal aspect through the correct use of the progressive periphrasis also the same learners who perform better in selecting the correct copula? Results revealed that familiarity with COPULA + ADJECTIVE pairs taught explicitly in the language classroom produced modest improvements in accuracy and speed. More importantly, learners who accurately rejected ungrammatical progressive constructions – demonstrating implicit sensitivity to aspectual constraints – also performed significantly better in copula selection. By contrast, frequency did not significantly predicted performance. These findings introduce the Cascade Interface Hypothesis, challenging purely usage-based models and supporting a generative-inspired interpretation.