Czech Aspect Mastery: Neotvírej!, přestal kouřit, annulled results
You know the aspect system's skeleton. This lesson adds the cartilage — the small choices that make Czechs stop noticing you're foreign.
Commands, Revisited
The full command matrix: positive one-off → perfective (Otevři okno!); prohibition → ne + imperfective (Neotvírej okno!). And the rare third row: a perfective prohibition is a sharp, specific warning — Neotevři to! — don't you dare open that.
Phase Verbs Demand Imperfective
začít (begin), přestat (stop), pokračovat (continue) only accept imperfective infinitives: Začalo pršet. Přestal kouřit — he quit smoking. You cannot begin or stop a completed action — the logic polices itself.
Přestal kouřit a začal běhat.
He quit smoking and took up running.
Note: Both phases, both imperfective infinitives — kouřit, běhat.
The Annulled Result
The connoisseur's distinction: Otevřel jsem okno — I opened the window (it's open now). Otvíral jsem okno — I had the window open… and it's closed again. The imperfective past can mean the result was undone.
Habits Stay Imperfective
However complete each instance, repetition runs imperfective: Každý den si kupuju kávu. Vždycky zapomínám klíče — I always forget my keys. One future slip, though, goes perfective: Zítra zapomenu — tomorrow I'll (surely) forget.
Common Mistakes
- začal udělat. Phase verbs refuse perfectives: začal dělat.
- Neotevři as the default don't. Everyday prohibitions run imperfective: neotvírej.
- Perfective habits. každý den + perfective clashes — habits flow imperfective.
What You Can Do Now
You can command, forbid and warn with intent, quit things grammatically, and deploy the annulled result — the aspect system's finishing school is behind you.