Forming Aspect Pairs: Suffixation and Secondary Imperfectives

Prefixation builds a perfective from an imperfective. Suffixation runs the machine in reverse: it builds an imperfective from a perfective, by adding a suffix to the verb stem. This is how Croatian produces the huge family of -ivati and -avati verbs you see everywhere — zapisivati, odlučivati, kupovati, dolaziti. The mechanism matters because it solves a problem prefixation creates. When a prefix adds meaning and makes a new perfective verb (pisati → zapisati "jot down"), that new verb has no imperfective partner yet — and suffixation is how Croatian gives it one. The result is the elegant three-step triad at the heart of the Croatian aspect system.

The secondary imperfective

Take a perfective verb and add an imperfectivising suffix, and you get a secondary imperfective — "secondary" because it is derived back from a perfective, rather than being a simple base verb. Its meaning is imperfective (process, repetition, habit), but its lexical content is whatever the prefixed perfective had.

The productive imperfectivising suffixes are -ava-, -iva-, -ova-, -ja- (the last often hidden inside stem changes). Compare:

The triad: simplex → prefixed perfective → secondary imperfective

Here is the structure that ties the whole system together. Many Croatian verbs sit in a three-step chain:

1. a simplex imperfective — the bare base verb (pisati "write");
2. a prefixed perfective — a prefix adds completion and often meaning (zapisati "jot down", potpisati "sign");
3. a secondary imperfective — a suffix re-imperfectivises that prefixed verb (zapisivati "jot down [habitually]", potpisivati "sign").

So the prefix perfectivised the verb; then, because Croatian still needs an imperfective for that new meaning, the suffix imperfectivised it again. Step 3 is the productive engine: once a verb is prefixed, the -iva-/-ava- suffix reliably gives it back an imperfective partner.

The suffix triggers sound changes

Adding an imperfectivising suffix often forces changes in the stem — jotation (a consonant softening before -j-) and ablaut (a vowel alternation). These are not random; they follow Croatian's regular jotation rules, but they make the imperfective look quite different from its perfective partner:

Suppletive pairs: when the two members are unrelated words

A few extremely common pairs are not built by either prefix or suffix — the two members are simply different roots that have come to function as an aspect pair. These are suppletive pairs, and because they are so frequent you must memorise them outright. (The fuller list is on the suppletive and bi-aspectual page.)

Strictly, dolaziti / doći and uzimati / uzeti are related historically, but for a learner they behave like suppletive pairs — the imperfective and perfective look nothing alike and must be learned as a unit.

Bi-aspectual verbs: one form for both aspects

Finally, a small but useful class of verbs are bi-aspectual (dvovidni glagoli): a single form serves as both imperfective and perfective, and only context tells you which is meant. Many are borrowings or -irati loanwords.

Common Mistakes

Key Takeaways

• Suffixation builds an imperfective from a perfective, using -ava-, -iva-, -ova-, -ja- — the productive imperfectivisers.
• The result is a secondary imperfective, completing the triad: simplex imperfective → prefixed perfective → secondary imperfective (pisati → zapisati → zapisivati).
• The suffix often triggers jotation or ablaut (skočiti → skakati, shvatiti → shvaćati) — the imperfective can look quite unlike its partner.
• Watch for suppletive pairs (govoriti / reći, uzimati / uzeti) and bi-aspectual verbs (ručati, telefonirati, organizirati) where one form covers both aspects.