In this article, the author shows that in the Basque Souletine dialect one currently finds both constructions of the passive type and antipassive type. Passive type constuctions are more common than antipassive type constuctions. The latter are, however, regarded as more adequate by the speakers. One can suppose that these constructions are older in the language. The author shows also how much it is important to study the linguistic structures and their frequency in the oral and written texts for better understanding of the Basque language, from the point of view of the dynamic synchrony.