In this article, we claim that syntactic objects undergoing ellipsis can be targeted by both narrow syntactic and PF operations. We base this conclusion on experimental evidence from the interaction between single conjunct agreement and verb-echo answers in South Slavic, which we show to be derived via verb-stranding VP ellipsis. Adopting the view that Vocabulary Insertion replaces Q-variables on lexical heads (Halle 1991) and ellipsis is a syntactic operation which deletes Q-variables (Saab 2022), we demonstrate that constituents properly included in the ellipsis site can undergo Internal Merge in the narrow syntax, and can participate in PF processes from the derived position. The interaction between ellipsis, Internal Merge and Agree-Copy that accounts for these patterns of data follows naturally within the Distributed Ellipsis approach.

We make these observations: (a) The direct embedding of a syntactic category X in itself (X-within-X) is surprisingly rare in human language, if it exists at all. (b) Indirect self-embedding (mediated by a sequence of other categories, and usually a phase boundary) systematically goes along with intensionality effects; the embedding and the embedded XP exhibit different behavior at the semantic interface. We argue that these constraints on recursion follow from the way in which single-cycle derivations organize semantic information in grammar.