Abstract
Complete rewrite of the STYX 2008 system: - improved rules for sentence filtering - improved transformations of syntactic trees to the school form - rewritten user interface - bugfixes STYX is an electronic exercise book of Czech based on data of the Prague Dependency Treebank. It consists of a console application used to filter unsuitable sentences (FilterSentences), an administrative application for creating exercises (Charon) and the exercise book itself, Styx.