Looking through the posts and grammar tips on this and other language sites I’ve noticed that the category of aspect of Russian verbs is often explained on the basis of so called “completeness” of the verbal process. I was greatly amazed at that. I cannot agree that the difference between the two aspectual verbal forms (perfective and imperfective) in Russian can be adequately explained with the help of this notion. I think that the point of view stated below represents the facts.

Any process of limited duration goes through the following three stages: the beginning, the going-on itself, and the end. A verbal process implying the achievement of either of the limits is expressed by a perfective verb. And on the contrary, a verbal process with no implication of its limit achieved or to be achieved is expressed by an imperfective verb.

In the oppositions петь – запеть, играть – заиграть, сиять – засиять the first element represents a process in its middle stage, while the second emphasizes its beginning. Such oppositions, however, do not constitute the category of the Russian aspect because they cover not the whole class of verbs but only relatively few of them. For instance, beginning is not expressed by the second element of the following pairs: лететь – залететь, писать – записать, чистить – зачистить.

Consider now the following oppositions: Он запел – Он запевал, Он подбежал – Он подбегал, Он достал платок – Он доставал платок. In запел emphasis is laid on the beginning, in подбежал on the end, in достал on both, because достал means neither начал доставать nor кончил доставать but represents the verbal process as a whole. The second element of the three pairs represents the process in its middle stage. This is true of the whole class of Russian verbs. Representation of processes with or without any emphasis laid on their limits constitutes, therefore, the grammatical category of aspect of the Russian language.

Broadly, aspect can be defined as a system of oppositions of different verbal forms referring to different modes of action.