摘要:This article examines the relation between aspect and object case in Estonian and establishes a verb classification that predicts many facets of object case behavior. It is demonstrated that the aspectual opposition between perfectivity and imperfectivity correspond to the morphological opposition between genitive/nominative case marking and partitive object case marking. However, case marking of Estonian objects is shown to be an unreliable indicator for aspectual verb class membership. The verb classification proposed here is established on the basis of tests that involve only the partitive object case. These tests employ the Estonian progressive. The tests distinguish verb classes from each other according to the situations they typically describe and predict several conditions of case assignment of patterns.