Earticle

In Korean that is an obligatorily tense marking language, the unconditional sentences have no tense or modality marker but the only sentential ending -ta. And the type of these sentences have several kinds of time reference, and are supposed to have a covert tense marker. However it does not satisfied conditions for zero morph which must have an exclusively expressed meaning in the tense system, so that can be interpreted as nothing. However in aspectual meanings, this sentential type has contrastiveness in the aspectual system with a portmanteau morpheme -nun- which is a cumulated tense-aspect marker and represents the non-past imperfective. So zero morph in verb predicates of unconditional sentences is a perfective aspect marker, but the adjective or copula predicates in these sentences have not a zero tense marker but a zero aspect maker.