Abstract
In some Slavic languages, there are relative pronouns formed from interrogative ones with the help of additional indicators, such as -to in Bulgarian, -r in Slovenian, što in Macedonian. Such pronouns occupy a different position in the systems of relativization of Slavic idioms, competing with relative pronouns that do not contain additional markers: in some languages (namely in contemporary literary varieties of Slovenian, Bulgarian and Lusatian), specialized relative pronouns occupy a central position in the system.
In some other languages (primarily in Czech and Polish), their use is limited to a few contexts, while there are other ones (literary Macedonian, as well as a number of non-literary Slavic idioms) with both specialized relative pronouns and pronouns coinciding with interrogative are widely represented in relative constructions. Despite significant differences in the status of specialized pronouns in the languages under consideration, it can be shown that their distribution obeys some similar patterns.
The emergence of markers is more characteristic of the left side of the semantic hierarchy of relative constructions proposed by A. Grosu and F.
Landman: "non-restrictive - restrictive - maximizing".