Almost every Croatian verb comes as a pair: an imperfective member and a perfective member that mean the same thing but view the action differently. Čitati and pročitati both mean „read"; pisati and napisati both mean „write". The imperfective looks at the action from the inside — as a process unfolding, a habit, an ongoing scene. The perfective looks at it from the outside, as a whole — a single bounded event with a result. This page is a quick chooser: given the situation, which member do you reach for? Each rule below comes with a contrastive pair so you can feel the difference, not just read it. For the underlying theory see the aspect overview; for the fuller decision tree see choosing the aspect.
The one question that decides most cases
Before reaching for a rule, ask: am I reporting a completed result, or a process / habit / ongoing scene?
- Completed result, a single whole event → perfective
- Process, repetition, habit, or a scene in progress → imperfective
| Situation | Aspect | Example |
|---|---|---|
| Finished it, there's a result | perfective | Pročitao sam knjigu. |
| Was busy doing it / used to do it | imperfective | Čitao sam knjigu. |
| Happening right now | imperfective only | Čitam knjigu. |
| A command to do it once | perfective | Pročitaj ovo! |
| A prohibition | imperfective | Nemoj čitati! |
Sinoć sam pročitao cijeli roman.
Last night I read a whole novel. — perfective 'pročitati': one bounded, completed event with a result.
Sinoć sam čitao u krevetu dok nisam zaspao.
Last night I was reading in bed until I fell asleep. — imperfective 'čitati': an ongoing process, no stated finish.
Completed result → perfective
If the action reached its endpoint and produced an outcome — you finished, you arrived, you wrote the whole thing — use the perfective. This is the aspect of „got it done".
Napisala sam mu poruku i poslala je.
I wrote him a message and sent it. — two perfectives: each act completed, with a result.
Konačno sam riješio taj problem.
I finally solved that problem. — perfective 'riješiti': the problem is now solved.
Process, habit, ongoing → imperfective
If you are describing the activity itself — what was going on, what you do regularly, what was unfolding — use the imperfective. No endpoint is in view.
Svako jutro pijem kavu na balkonu.
Every morning I drink coffee on the balcony. — imperfective 'piti': a habit, repeated action.
Pisao sam taj rad tri tjedna.
I was writing that paper for three weeks. — imperfective 'pisati': duration of the process; 'napisao' would claim it's finished.
Present time „right now" → imperfective only
This is the rule with no exceptions: the perfective has no real present-time meaning. A perfective present-tense form does not say „I am doing it now" — it points to the future or to a hypothetical. So whenever you mean „I'm doing this at this moment", you can only use the imperfective.
Što radiš? — Spremam večeru.
What are you doing? — I'm making dinner. — present-now requires the imperfective 'spremati'.
Upravo izlazim iz kuće, stižem za deset minuta.
I'm just leaving the house, I'll be there in ten minutes. — imperfective for the action in progress now.
A perfective present like spremim or izađem does not mean „I'm preparing / I'm leaving now" — it lands in the future or inside a da-clause (kad spremim večeru „once I've made dinner"). That is why the present tense of a perfective is never the answer to „what are you doing?"
After begin / stop / continue (phase verbs) → imperfective
Verbs that frame a phase of an action — početi („begin"), prestati („stop"), nastaviti („continue") — take the imperfective for the action they frame. The logic is airtight: you can only begin, stop, or continue a process, and a process is imperfective. You cannot „begin to read-it-all-the-way-through" in one bounded gulp.
Počeo je čitati i nije mogao stati.
He started reading and couldn't stop. — phase verb 'početi' takes the imperfective 'čitati'.
Prestani vikati na mene!
Stop yelling at me! — 'prestati' takes the imperfective 'vikati'.
Nastavila je raditi i nakon ponoći.
She kept working even after midnight. — 'nastaviti' + imperfective 'raditi'.
There is no *počeo je pročitati — pairing a phase verb with a perfective is ungrammatical. This is one of the cleanest, most predictable aspect rules in the language.
Commands: positive → perfective, prohibition → imperfective
In the imperative the two aspects split by polarity. A positive command to do something once is normally perfective („do it, finish it"). A prohibition („don't…") is normally imperfective, because you are telling someone not to engage in the activity at all.
| Positive command (perfective) | Prohibition (imperfective) |
|---|---|
| Zatvori prozor! (Close the window!) | Ne zatvaraj prozor! (Don't close the window!) |
| Pojedi to! (Eat that up!) | Nemoj to jesti! (Don't eat that!) |
| Reci mi! (Tell me!) | Ne govori mi to! (Don't tell me that!) |
Otvori vrata, molim te.
Open the door, please. — positive one-off command: perfective 'otvoriti'.
Nemoj otvarati vrata nikome.
Don't open the door to anyone. — prohibition: imperfective 'otvarati'.
This is a strong tendency, not an absolute law — a positive imperfective command exists when you mean „keep doing it / do it generally" (Čitaj svaki dan! „Read every day!"). The fuller picture is on aspect in the imperative.
Narrative: sequence → perfective chain, background → imperfective
When you tell a story, the two aspects do two different jobs. A sequence of events that moves the plot forward — this happened, then that happened — is a chain of perfectives. The background scene against which those events occur — what was going on, the weather, what people were doing — is imperfective.
Ušao je, skinuo kaput i sjeo za stol.
He came in, took off his coat and sat down at the table. — three perfectives: a sequence of completed events advancing the story.
Padala je kiša, a ljudi su žurili kući.
It was raining, and people were hurrying home. — imperfectives: the standing background scene, not plot-advancing events.
Spavao sam kad je zazvonio telefon.
I was sleeping when the phone rang. — imperfective background 'spavao', perfective interrupting event 'zazvonio'.
Common Mistakes
❌ Što pročitaš? (asking what someone is reading now)
Incorrect — a perfective present can't mean 'right now'; use the imperfective for the action in progress.
✅ Što čitaš?
What are you reading? — imperfective for present-time action.
❌ Počeo je pročitati knjigu.
Incorrect — phase verbs ('početi') take the imperfective; you can only begin a process.
✅ Počeo je čitati knjigu.
He started reading the book.
❌ Nemoj zatvoriti prozor.
Dispreferred — a prohibition normally takes the imperfective.
✅ Nemoj zatvarati prozor.
Don't close the window.
❌ Pisao sam pismo i odmah ga poslao. (meaning: I wrote the whole letter, then sent it)
Mismatch — for a completed result the perfective 'napisao' is wanted; imperfective 'pisao' describes only the process.
✅ Napisao sam pismo i odmah ga poslao.
I wrote the letter and sent it right away. — two completed events.
Key Takeaways
- The master question: completed whole-event result → perfective; process / habit / ongoing scene → imperfective.
- Present time „now" is imperfective only — the perfective present points to the future, never to the moment of speaking.
- Phase verbs (početi, prestati, nastaviti) always take the imperfective — you can only begin/stop/continue a process.
- Commands split by polarity: positive one-off → perfective (Zatvori!); prohibition → imperfective (Nemoj zatvarati!).
- In narrative, chain perfectives for the events that advance the story and use imperfectives for the background scene (Padala je kiša kad je ušao).
Related Topics
- Verbal Aspect: The Big PictureA2 — Why nearly every verb comes in an imperfective/perfective pair.
- Choosing the Right Aspect: A Decision GuideB1 — A practical procedure for picking imperfective vs perfective.
- Aspect in the ImperativeB1 — Why positive commands go perfective and prohibitions go imperfective.
- da + present vs the InfinitiveB1 — When to use the infinitive and when to use a da + present clause after modal and volition verbs — the same-subject choice, the different-subject rule, and the register split.