Featural Relativized Minimality in silence: the acquisition of sluicing in Italian

This paper investigates the acquisition of elliptical indirect wh questions, i.e. sluicing, by Italian preschool children. The goal is to determine whether children’s comprehension of subject and object extracted sluices is also modulated by the locality principle of featural Relativized Minimality (fRM; Rizzi 2004; 2018) as is the case with lexicalized wh questions. Adopting Merchant's (2001) structural approach to ellipsis, we designed three related experiments. Experiment 1 compares the comprehension of lexicalized and sluiced indirect wh questions, aiming at verifying the presence of the subject>object asymmetry well-documented in the acquisition studies of other A'-dependencies. A subject advantage is detected in both elliptical and non-elliptical questions. To verify the role of fRM, Experiments 2 and 3 manipulate the degree of featural overlap between the wh remnant and the other unpronounced DP in the sluice. We targeted Lexical Restriction (Experiment 2) and Number feature (Experiment 3). Our findings further confirm the subject>object asymmetry and, more crucially, demonstrate that children's difficulties with object sluices are alleviated when the subject and object are featurally mismatched, as predicted under fRM. We conclude that this locality principle regulates the acquisition of dependencies independently of their PF realization. Our study further corroborates an analysis of sluicing in terms of full fledged interrogative structures isomorphic to their antecedent (e.g., Merchant 2001).