In the Lithuanian language, prefixing of a simple verb does not always lead to perfective aspect, nor is, there general way of forming imperfective from prefixed perfective verb, such as at an early stage in the development of the Slavonic languages. Therefore, there are only few purely aspectual pairs of verbs with semantically empty prefixes.
Most prefixed verbs, which are usually considered as perfective, can be interpreted as morphologically marked terminative (telic) verbs. This is the reason why Lithuanian contains a number of so -called neutral verbs which can express both imperfective and perfective aspect, mainly according to tense. In the Lithuanian tense -aspect system important parts are played by four simple tense forms (in the active voice) and four compound tense forms (both in the active and passive voice).
Both perfect and imperfect of the compound tenses have determinations of 'phase', ‹terminalization› and ‹intraterminalization›, respectively. Terminative: aterminative (telic: atelic) character of verbs has an interaction mainly with these basic meanings of perfect and imperfect, which accounts for various aspectual meanings and 'taxis' functions of the Lithuanian compound tenses.
