EN
An analysis of examples of the past perfect tense composed of a singular and plural past tense participle and an aorist form of the ‘to be’ verb in the singular third person form used as an auxiliary word is given in the article. The author, referring to the research of W.R. Rzepka, presents three consecutive examples from the mediaeval court oaths, where the aorist by has the meaning of ‘był’ (past form of the to be verb in Polish).