EN
In this paper, I discuss the aspectual system of Czech and in particular, the prefix combinations in verbs. Following the arguments of Gehrke (2009) and the general model of Zwarts (2005), I argue that as upward monotone vectors, the goal prefixes do- and při- cannot be modified by the measure prefix po- (there are no verbs such as *po-do-skočit or *po-při-jet). I then offer a formal treatment of paths and events homomorphism for motion verbs in Czech. Based on the examined data, I argue in favor of keeping separate two distinctions in the aspectual system of Czech: telicity and perfectivity. The paper as a whole is dedicated to the integration of the formal treatment of Czech aspect with vector space semantics for preposition phrases and prefixes.