Abstract : This paper aims at showing that the old imperfective periphrasis of Basque [verbal noun + locative + izan “to be”/ *edun “to have”] should be the result of a metaphorical use of a locative expression with noun verbs. When this construction was reanalysed as an aspectual periphrastic construction, an actualization process caused the realignment of the structure, extending the ergative case and the auxiliary *edun “to have” to the transitive verbs. This hypothesis seems to be confirmed by the synchronic data of the new progressive structure of Basque and by the evolution of others ergative languages.
