Suppletive Aspectual Pairs
Most aspectual pairs in Croatian share a root, changing only by adding a prefix or altering a suffix. However, a few very common verbs use completely different words for the ongoing action (imperfective) and the completed action (perfective). These are called "suppletive" pairs.
Looking and Listening
Use the imperfective gledati (to look) when directing your attention, and the perfective vidjeti (to see) when successfully perceiving it.
Similarly with sound: making the effort to listen is the imperfective slušati, while actually perceiving the noise is the perfective čuti (to hear).
Speaking and Saying
For the ongoing action of speaking, use the imperfective govoriti. For a completed statement—such as delivering a specific message or a piece of news (vijest)—use the perfective reći (to say or tell).
Messages and Arrivals
Some verbs undergo significant stem changes. Slati (to send, ongoing) pairs with poslati (to send, completed). Dolaziti (to arrive, ongoing) pairs with the shorter perfective doći (to arrive, completed).
Telling Stories
The imperfective pričati generally means "to talk." By adding a prefix, we get ispričati, meaning "to tell" a complete story (priča) from beginning to end (perfective).
Finally, notice how these verbs of speaking, hearing, and seeing are used together to contrast unfolding events with sudden, completed actions.
