# Patterns of imperfective/perfective



## Kwunlam

Ahoj ! 

I would like to ask a question. I could see that *psat *(impf.)/*napsat *(pf.) forms an imperfective-perfective  pair. But then I could see that přede*psat* is also perfective, while the corresponding imperfective form is přede*pisovat*. So the pair is *předepisovat/předepsat*. My question is, is there a way to predict the form of "předepisovat"? Where does this "posivat" suddenly come from?



I have this question also for motion verbs. 
*jít/chodit *are both imperfective, 
but *přicházet/přijít *forms an imperfective-perfective pair with some spelling changes. Are there special rules (or at least some inductive generalisations) concerning these spelling changes?


Thank you very much!


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## bibax

The perfective verbs are commonly created from the imperfective non-prefixed verbs by adding a prefix. However adding prefix to an imperfective verb often changes its meaning. Thus the corresponding prefixed imperfective verb must be created by a suffix, usually by -ovat.

psát > odepsat > odepisovat
psát > podepsat > podepisovat
psát > zapsat > zapisovat
psát > vypsat > vypisovat
psát > přepsat > přepisovat
psát > sepsat > sepisovat

but

psát > napsat > napisovat
(as napsat has quite the same meaning like psát, only with different verbal aspect, there is no need for napisovat)

When an imperfective verb has an iterative counterpart the pattern is somewhat different.

jít (imperf., chodit iter.) > přijít (perf.) > přicházet (imperf.)
nést (nosit) > přinést > přinášet
vést (vodit) > přivést > přivádět
vézt (vozit) > přivézt > přivážet
...


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## werrr

Kwunlam said:


> My question is, is there a way to predict the form of "předepisovat"? Where does this "pisovat" suddenly come from?


There are some general rules for some verbal classes, typically *-at* turns into *-ovat*, but there is also a lot of historical irregularites. The problem with the verb *psát* is that it underwent a specific shortening from original form *pisati* to *psáti*. This change needn't be reflected in the other derived forms, so *-pisovati* is actually regular counterpart of the original form *pisati*.



> I have this question also for motion verbs.
> *jít/chodit *are both imperfective,
> but *přicházet/přijít *forms an imperfective-perfective pair with some spelling changes. Are there special rules (or at least some inductive generalisations) concerning these spelling changes?


Irregularity once again. The conjugation of the verb *jít* and its derivatives is historically a mix of verbs with completelly different word stems alike English *to go* turning into *went*.


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## Kwunlam

Thank you very much for your explanations!


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## Enquiring Mind

The wordreference.com experience, in a nutshell (česká verze)

A foreigner working in Prague
Said "I find I'm increasingly vague
About aspects. It's so
Complicated, I know,
But could someone boil it down into a couple of handy easy-to-remember sound bites please? Děkuji předem!"


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