The Russian verb has 3 tenses and 2 aspects. Aspects describe different qualities of an action—it is either acting (the process of doing something—Imperfective) or the result of an action (after someone has finished doing something—Perfective). Using the Imperfective/Perfective depends only on the intention of the speaker to emphasize different aspects of action in his or her speech.
Imperfective aspect is used for: repeated or habitual actions (in the present, past and future), incomplete, ongoing, habitual, reversed or repeated actions.
Perfective aspect is used for: a single, completed action in the past.
The perfective aspect is not created by changing the ending. There are normally two words for each verb. One is the imperfective, the other is the perfective. Often these two words are closely related, but this is not always the case. (Often the perfective is simply prefixed with “По”). If you look at the conjugated verbs list on this site you can see some examples of how verbs are conjugated in both aspects. Here are some examples of verb pairs.
(Imperfective, Perfective)
Жить, Прожить – live
Любить, Полюбить – love
Делать, Сделать – do, make
Говорить, Сказать – talk, speak, say.
Работать, Поработать – work
The Perfective can be used only in the Past or Future Tense, since the result can be either reached in past, or it will be reached in future. Russians use the Imperfective for the Present Tense, since the present is in progress.
If you require emphasizing in your speech a necessity of fulfillment or a desire to finish an action and achieve a result—use the Perfective: Я сделаю это к вечеру. Мы напишем отчёт через неделю.
If you need to say that the process of doing something is necessary and important, then use the Imperfective: Я буду заниматься спортом. Он будет говорить с директором после обеда.
Using an imperfective verb you can form the Present tense, the Past tense and the Future tense.
A perfective action is possible only in the Past or Future, because the idea of completion is incompatible with the Russian conception of present tense.
| Aspect/Tense | Past | Present | Future |
| Perfective | Он прочитал эту книгу. He has read this book. ( ‘finished reading’ – the completion is emphasized) |
– |
Он прочитает эту книгу. He will have read this book. (the intention to complete is emphasized) |
| Imperfective | Он читал книгу. He was reading / read a book. (the result is not emphasized ) |
Он читает книгу. He is reading a book. (now )Вечером он часто читает.In the evening he often reads. (a habitual action) |
Он будет читать книгу. He will be reading / will read a book. (the intention to complete is not emphasized) |
Adverbs like обычно, часто, редко, всегда, иногда (usually, often, rare, always, sometimes) and time expressions like каждый день, каждый год, каждую неделю (every day, every year, every week) indicate repetition and therefore require an imperfective verb.
Я всегда завтракаю дома (I always have breakfast at home).
Он работает каждый день (He works every day).
The word уже (already) indicates completion and therefore requires a perfective verb.
Она уже приготовила ужин (She has already prepared dinner).
The perfective aspect is formed form the imperfective by prefixation. This does not effect conjugation type:
| mperfective Aspect | Perfective Aspect | Translation | |
| читать писать рисовать печатать звонить смотреть завтракать обедать ужинать слушать делать готовить |
прочитать написать нарисовать напечатать позвонить посмотреть позавтракать пообедать поужинать послушать сделать приготовить |
have read have written have drawn have printed have called/phoned have watched have eaten breakfast have eaten lunch have eaten dinner to have listened have done have cooked/prepared |
The perfective aspect is formed form the imperfective by suffixation with the possible mutation of final root consonant or truncation of prefix. Conjugation type changes. Note the pairing a 1st conjugation verb (imperfective) with a 2nd conjugation verb (perfective).
| Imperfective Aspect | Perfective Aspect | Translation | |
| решать покупать отвечать |
решить купить ответить |
to solve, decide -> have solved/decided to buy -> have bought to answer -> have answered |
Some verbs have different roots or different stems for im perfective and perfective aspects. Examples:
| Imperfective Aspect | Perfective Aspect | Translation | |
| говорить переводить | сказать перевести | to tell/say – have told/said to translate – have translated |