The topic of this thesis is the verbal aspect in its complexity. The initial theoretical part aims to compare the differences in the notion of grammatical and lexical aspect in both Italian and Czech language and to highlight the differences in related terminology. The following practical part deals with Italian periphrastic passive and its auxiliaries venire and essere from aspectual point of view based on the Czech language. It is generally assumed that at least in the present tense, passive constructions containing the auxiliary venire should be translated into Czech with higher rate of imperfective verbs than passive constructions containing the auxiliary essere. This trend should disappear when used in the simple past or the imperfect. This claim is further analyzed with the help of the parallel corpus InterCorp, version 10.