EN
This article examines selected variations in spoken Czech in two sub-corpora of the Czech National Corpus: the Prague Spoken Corpus (PSC) and the Brno Spoken Corpus (BSC). These include the prothetic 'v-' at the beginning of words starting with 'o-', variations in case endings of hard stem adjectives and the third person indicative plural endings in major verb classes, as well as the usage of the personal pronoun 'já' and/or the auxiliary verb 'jsem' in the past tense forms. Our interpretation of changes in apparent time is checked against data from the relevant literature. The most significant change is the decline of the prothetic 'v-' in the BSC, reported for Brno earlier by Krcmová (1981, 1997). We show that it is female speakers who are leading this change. The PSC informal speech is stable, while a significant shift toward colloquial variants has been identified in formal discourse. In the past tense, the form without the auxiliary 'jsem' is rare except for 'já myslel(a)' in the PSC.