The paper is focused on questions of the textual distribution of the so-called enclitic -s in Czech. The past tense form of the 2nd person singular of the auxiliary verb být (to be) can in some cases be represented by the shortened form -s instead of its basic form jsi.
This element can be added as a suffix directly to the form of the lexical verb l-participle (přišel jsi } přišels) or to some another word in the sentence (Petra jsi neviděl? } Petras neviděl?). Because the target forms are specific primarily to spontaneous dialogue, the analysis presented is based on the material of two corpora of informal spoken Czech - ORAL2006 and ORAL2008.
The analysis attemps to describe the textual distribution of the enclitic -s in terms of its basic constraints, e.g to ascertain and describe the positions where it is impossible for -s to occur. The structural principle applied in this analysis is based primarily on part-of-speech affiliation and syntactic position (in relation to lexical verb of the sentence, e.g. l-participle) of the textual word to which the -s element can or cannot be added.