Prefixes mostly build perfectives (чита́ти → прочита́ти; see the prefix page). Suffixes do the opposite job: they build imperfectives, by taking a perfective and inserting an imperfectivizing suffix — chiefly -а-, -ува-, or -ову-. да́ти (perfective "give") → дава́ти (imperfective); купи́ти (perfective "buy") → купува́ти (imperfective). So the system as a whole has a tidy shape: prefix-for-perfective + suffix-for-imperfective. This page covers the suffixes, the consonant and vowel alternations that ride along with them, and the small set of suppletive pairs that follow no rule at all and must simply be memorised.
The mechanism: a suffix that "stretches" a perfective into a process
A perfective like купи́ти packages buying as a single completed act. To talk about buying as a process or a habit — "I'm buying / I buy regularly" — you need an imperfective, and Ukrainian makes one by suffixation: купи́ти → купува́ти. The suffix -ува- stretches the bounded event back out into an open-ended activity. This second imperfective, derived from a perfective, is a secondary imperfective (see secondary imperfectives).
Я купи́в нову́ ку́ртку — а взага́лі купу́ю о́дяг ду́же рі́дко.
I bought a new jacket — though generally I buy clothes very rarely. (купи́в perfective single act; купу́ю, from imperfective купува́ти, the habit.)
Хто дасть мені́ ру́чку? — Я за́вжди даю́ свою́, а по́тім не знахо́джу.
Who'll give me a pen? — I always give mine away, and then can't find it. (дасть perfective да́ти; даю́, from imperfective дава́ти, the habit.)
The main imperfectivizing suffixes
The productive suffixes are -ува-/-юва-, -ову-, and plain -а-/-я-. Here are high-frequency pairs; note that the perfective is usually the shorter, "tighter" member and the imperfective the longer, suffixed one:
| Perfective | Imperfective (suffixed) | Meaning | Suffix / change |
|---|---|---|---|
| да́ти | дава́ти | to give | -ва- |
| купи́ти | купува́ти | to buy | -ува- |
| показа́ти | пока́зувати | to show | -ува- |
| забу́ти | забува́ти | to forget | -ва- |
| відкри́ти | відкрива́ти | to open | -ва- |
| записа́ти | запи́сувати | to write down / record | -ува- |
| переписа́ти | перепи́сувати | to rewrite | -ува- |
| ви́рішити | вирі́шувати | to decide / solve | -ува- |
Я тобі́ вже пока́зувала ці фо́то? — Покажу́ ще раз, диви́сь.
Have I shown you these photos already? — I'll show them once more, look. (пока́зувала, imperfective 'naming the activity'; покажу́, perfective показа́ти, future result.)
Не вмика́й кондиціоне́р — я щора́зу забува́ю його́ ви́мкнути, а ти не забу́дь.
Don't switch on the AC — I forget to turn it off every time, but you don't forget. (забува́ю, imperfective habit; забу́дь, perfective забу́ти.)
Вони́ щодня́ відкрива́ють крамни́цю о во́сьмій, а сього́дні відкри́ли о деся́тій.
They open the shop at eight every day, but today they opened at ten. (відкрива́ють, imperfective habit; відкри́ли, perfective single event.)
Consonant mutations in the imperfectivizing stem
When the imperfectivizing suffix attaches, the stem-final consonant often mutates — the same kinds of alternations you meet in the present tense. The frequent ones:
- т → ч: зустрі́ти → зустріча́ти "to meet"; відповісти́ → відповіда́ти (here д → д but cf. the т-group) — and поверну́ти → поверта́ти keeps т.
- с → ш: запроси́ти → запро́шувати "to invite"; the с of the perfective surfaces as ш before -ува-.
- д → дж / жд: as in many derived imperfectives of -дити verbs.
Ми зустріча́ємося щоп’я́тниці, а цього́ ра́зу зустрі́лися аж у се́реду.
We meet up every Friday, but this time we met as early as Wednesday. (зустріча́ємося imperfective habit, т→ч; зустрі́лися perfective single event.)
Вона́ ча́сто запро́шує госте́й, а на день наро́дження запроси́ла аж со́рок осі́б.
She often invites guests over, and for her birthday she invited as many as forty people. (запро́шує imperfective, с→ш; запроси́ла perfective.)
Root-vowel alternations: о/и and е/и
A systematic and very common pattern: forming the imperfective lengthens the verb and alternates the root vowel — a "tighter" о or е in the perfective becomes и in the imperfective. These are not random; they are an old regular alternation, and recognising it lets you predict whole sets.
| Perfective | Imperfective | Meaning | Alternation |
|---|---|---|---|
| зібра́ти | збира́ти | to gather / collect | и appears in the root |
| назва́ти | назива́ти | to name / call | ‑зв‑ → ‑зив‑ |
| поме́рти | помира́ти | to die | е → и |
| запе́рти | запира́ти | to lock | е → и |
| посла́ти | посила́ти | to send | ‑сл‑ → ‑сил‑ |
Восени́ ли́стя помира́є краси́во — а цей кущ, зда́ється, по́вністю поме́р.
In autumn the leaves die beautifully — but this bush, it seems, has died completely. (помира́є imperfective process, root и; поме́р perfective result, root е.)
Щовесни́ ми збира́ємо чере́шні всі́єю роди́ною, а цьогорі́ч зібра́ли два відра́ за годи́ну.
Every spring we pick cherries as a whole family, and this year we gathered two buckets in an hour. (збира́ємо imperfective habit; зібра́ли perfective result.)
The suppletive pairs: no rule, just memory
A small but extremely high-frequency group forms its aspect pair from two different roots — there is no prefix or suffix relationship at all. These are suppletive, like English go/went or good/better, and you simply have to learn them as fixed pairs.
| Imperfective | Perfective | Meaning |
|---|---|---|
| бра́ти | взя́ти | to take |
| говори́ти / каза́ти | сказа́ти | to say / speak |
| лови́ти | спійма́ти / злови́ти | to catch |
| кла́сти | покла́сти | to put / lay |
| шука́ти | знайти́ | to look for / find |
A couple of these are only partly suppletive: лови́ти / злови́ти share a root (just a prefix apart), while лови́ти / спійма́ти are fully suppletive — both are used, спійма́ти being especially common for "catch (and succeed)". And говори́ти / каза́ти / сказа́ти is a three-way knot: говори́ти and каза́ти are both imperfective ("speak / say"), and сказа́ти is the perfective partner of каза́ти. See бра́ти / взя́ти and говори́ти in the verb reference for full paradigms.
Я за́вжди беру́ парасо́льку, а сього́дні взяв і — звича́йно — не знадоби́лась.
I always take an umbrella, and today I took one and — of course — didn't need it. (беру́, from imperfective бра́ти; взяв, perfective взя́ти — a different root entirely.)
Скі́льки разі́в я тобі́ каза́ла? Я сказа́ла оди́н раз — і ти забу́в.
How many times have I told you? I said it once — and you forgot. (каза́ла imperfective repeated; сказа́ла perfective single act — suppletive.)
Ми вже годи́ну лови́мо таксі́, і наре́шті я спійма́в одне́ на ро́зі.
We've been trying to catch a taxi for an hour, and I finally caught one on the corner. (лови́мо imperfective ongoing effort; спійма́в perfective success — suppletive.)
Source-language comparison
For an English speaker, the suffix mechanism is the harder of the two to internalise, because English has no parallel: we don't "lengthen" a verb to make it habitual. The mental model that helps: the perfective is the basic, tight event (купи́ти, да́ти, поме́рти) and the imperfective is built from it by padding it out with a suffix (купува́ти, дава́ти, помира́ти) — the reverse of the prefix story, where the imperfective is basic. The vowel alternations (о/и, е/и) and consonant mutations (т→ч, с→ш) are systematic enough to recognise, but the suppletive pairs (бра́ти/взя́ти, каза́ти/сказа́ти) are pure memory, like English go/went.
For a Russian speaker, the suffix system is structurally familiar (Russian likewise uses ‑ыва‑/‑ива‑, ‑ва‑, ‑а‑ and the same suppletive pairs брать/взять, говорить/сказать). Relearn the Ukrainian forms and stress — пока́зувати, запи́сувати, помира́ти — and a few divergent pairs; the machinery transfers.
Common Mistakes
❌ Я щодня́ покажу́ йому́ нові́ слова́. (perfective for a daily habit)
Wrong — a habit is imperfective, and покажу́ is a future. Use the secondary imperfective: Я щодня́ пока́зую йому́ нові́ слова́.
✅ Я щодня́ пока́зую йому́ нові́ слова́.
I show him new words every day. (пока́зувати, imperfective habit.)
❌ Я за́раз дам тобі́ зна́ти. (perfective future for an action happening 'right now')
For an ongoing 'now', use the imperfective дава́ти → даю́. (As a promise, дам is a fine perfective future 'I'll let you know'.) For 'I'm letting you know now': Я за́раз даю́ тобі́ зна́ти.
✅ Я за́раз даю́ тобі́ зна́ти.
I'm letting you know now. (даю́, imperfective present.)
❌ Я ча́сто взяв таксі́ додо́му. (perfective взя́ти with 'often')
Mismatched — 'often' is habit, which needs the imperfective бра́ти: Я ча́сто беру́ таксі́ додо́му.
✅ Я ча́сто беру́ таксі́ додо́му.
I often take a taxi home. (беру́, from imperfective бра́ти.)
❌ Ми щоп’я́тниці зустрі́немося в кав’я́рні. (perfective for a weekly routine)
Wrong — a weekly routine is imperfective, and зустрі́немося is a future. Use: Ми щоп’я́тниці зустріча́ємося в кав’я́рні.
✅ Ми щоп’я́тниці зустріча́ємося в кав’я́рні.
We meet up at the café every Friday. (зустріча́тися, imperfective habit, т→ч.)
Key Takeaways
- Suffixes build the imperfective from a perfective — the reverse of prefixation. The productive suffixes are -ува-/-юва-, -ову-, -ва-, -а-/-я-: да́ти→дава́ти, купи́ти→купува́ти, показа́ти→пока́зувати, забу́ти→забува́ти, відкри́ти→відкрива́ти.
- The suffix often triggers a consonant mutation (зустрі́ти→зустріча́ти т→ч; запроси́ти→запро́шувати с→ш) or a root-vowel alternation (зібра́ти→збира́ти, назва́ти→назива́ти, поме́рти→помира́ти) — both systematic.
- The whole pairing system: prefix-for-perfective + suffix-for-imperfective.
- A small, high-frequency group is suppletive — two different roots, no rule: бра́ти/взя́ти, говори́ти·каза́ти/сказа́ти, лови́ти/спійма́ти, кла́сти/покла́сти, шука́ти/знайти́. Memorise them outright.
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Start learning Ukrainian→Related Topics
- Verbal Aspect: The Big PictureA2 — Aspect is the central, pervasive feature of the Ukrainian verb: nearly every verb belongs to an aspect PAIR — imperfective (недоко́наний вид), which views an action as a process, ongoing, repeated, or general (чита́ти), and perfective (доко́наний вид), which views it as a single completed whole with a result or boundary (прочита́ти). The consequences are sharp: imperfectives have a present, a past, and BOTH futures (бу́ду чита́ти / чита́тиму); perfectives have NO present — their present-shaped form is future (прочита́ю = 'I will read it through') — only a past (прочита́в) and a simple future (прочита́ю). Aspect is chosen for EVERY verb in EVERY clause; it is not optional, and it has no English equivalent.
- Forming Aspect Pairs: PrefixesB1 — The most common way to build a perfective is to add a 'pure' perfectivizing prefix to the imperfective: чита́ти→прочита́ти, писа́ти→написа́ти, роби́ти→зроби́ти, ї́сти→з’ї́сти, пи́ти→ви́пити. The frequent perfectivizing prefixes are про-, на-, з-/с-/зі-, по-, ви-, при-. The catch: the SAME prefixes can instead add lexical meaning and make a NEW verb (писа́ти→переписа́ти 'rewrite'), so you must learn to tell aspect-only prefixation from meaning-changing prefixation.
- Secondary Imperfectives and Aspect TripletsB2 — How a prefixed perfective spawns its own imperfective via -ува-/-юва-/-а- (переписа́ти → перепи́сувати), producing aspect 'triplets' (писа́ти → переписа́ти → перепи́сувати) — the engine that keeps every prefixed verb aspectually paired, plus the о/и and е/и root alternations (зібра́ти → збира́ти) that ride along with it.
- Давати / Дати (to give)A1 — Complete conjugation-and-usage reference for the aspect pair дава́ти (imperfective) / да́ти (perfective) 'to give'. The imperfective дава́ти is a regular -ва- present (даю́, дає́ш, дає́…); the perfective да́ти is one of the four ATHEMATIC verbs of Ukrainian, with the irregular set дам, даси́, дасть, дамо́, дасте́, даду́ть that means the FUTURE, not the present. Recipient in the DATIVE (дай мені́), thing given in the ACCUSATIVE (да́ти кни́жку), plus the everyday дай / дава́й imperatives.
- Брати / Взяти (to take)A2 — Complete conjugation-and-usage reference for the suppletive aspect pair бра́ти / взя́ти 'to take'. The imperfective бра́ти builds its present on a hidden бер- stem (беру́, бере́ш, бере́…), while the perfective взя́ти supplies a completely different future (візьму́, ві́зьмеш…). Covers the gendered past (брав / брала́ … узя́в / взяла́), both imperfective futures, the imperative (бери́ / візьми́), case government (accusative object), and the high-frequency idioms бра́ти у́часть 'take part' and взя́ти себе́ в ру́ки 'pull oneself together'.
- Купувати / Купити (to buy)A2 — Complete conjugation-and-usage reference for the aspect pair купува́ти (imperfective) / купи́ти (perfective) 'to buy'. The imperfective купува́ти is a textbook -ува-/-у- verb (купу́ю, купу́єш, купу́є…); the perfective купи́ти is a second-conjugation -и- verb with the labial mutation п→пл in the 1sg куплю́ and 3pl ку́плять (but plain ку́пиш, ку́пить). Object in the ACCUSATIVE (купи́ти хліб), recipient in the DATIVE (купи́ти пода́рунок ма́мі), and the GENITIVE PARTITIVE for 'some' (купи́ти цу́кру).