Imperfectivity and Transience The Two Sides of the Progressive Aspect in Simultaneity as- and while-clauses

Recent research into simultaneity as- and while-clauses has shown that they tend to be used differently. As-clauses usually code events with a high degree of susceptibility to change, whereas while-clauses tend to evoke more stable temporal configurations. Following this insight, the present article studies the interaction between the progressive aspect and as- and while-clauses. It is claimed that the progressive aspect in as-clauses is prototypically used as a slowing-down/stretching device (i.e., an imperfectivization mechanism). It is used to establish an aspectual contrast between a prolonged as-event and a (relatively) punctual main event. By contrast, progressive while -clauses seem to behave more similarly to main clauses. The progressive is primarily used as a transience marker, that is, to signal that the (relatively) stable event coded by a while-clause is a temporary state.