Agreement and the structure of relative clauses

The paper proposes an account of asymmetries in agreement patterns that obtain in restrictive and non-restrictive relative clauses headed by hybrid agreement nouns 'd(j)eca '‘children’, 'braća '‘brothers’, and 'gospoda '‘gentry’ in Bosnian/Croatian/Serbian (BCS). We note that relative clauses headed by hybrid nouns display different possibilities of agreement morphology on the relative pronoun 'koji/a/e '‘which’, depending, on the one hand, on whether the relative clause is restrictive or non-restrictive and on the other, on the case of the relative pronoun. We argue that the observed differences are the result of a conspiracy of the following factors: (i) hybrid number-agreement nouns introduce a null plural pronoun unspecified for gender (Postal 1966; den Dikken 2001; Torrego and Laga 2015), (ii) all plural case forms of the relative pronoun except for nominative and accusative show full gender syncretism (Alsina and Arsenijević 2012b), and (iii) non-restrictive relative clauses involve a null definite pronoun and attach to the head noun higher than the restrictive relative clauses (Postal 1994; de Vries 2002; 2006). We maintain that the facts discussed in the paper argue against analyses which derive the differences between restrictive and non-restrictive relative clauses from their LF representations, rather than from their overt syntax