In German, relative clauses as attributes to 1st or 2nd person personal pronouns are rare, complex and hard to learn: Ich, der ich gern koche, stelle hohe Ansprüche. In real life communication simpler structures are often used: Ihr, die malen lernt, besucht jede Ausstellung. These structures are little studied, do not figure in regular reference grammar books, but are attested experimentally. In the relevant structures, the morphological features diverge between head pronoun (2nd Ps) in the matrix clause and the subject (3rd Ps) and the finite verb (2nd Ps) in the RC. The experimental survey will be aimed at clefts: Ihr seid es, die malen lernen/??lernt and other similar and related constructions. German, Polish and Italian will be investigated, since these languages have specific properties, differing in the relevant points, and thus promising insights. Since the state of research is very different for each language, different approaches and weightings result in the heuristics for aspireddata collection (classical questioning/assessment of structures, psycho-linguistic experiments: self-paced reading, eye tracking, event-related potentials). A synthesis of the results aims at a coherent picture on different languages and grammatical processes. Besides the ostensibly empirical collection of concrete data, the theoretical goal is to contribute to the syntactic analysis of relative-clause-like constructions and to the morpho-syntactic analysis of congruence or agreement.