Learn Croatian: Prespavala je, tako da kasni na posao. - She overslept, so she is late for work.

The base verb is spavati (to sleep). In this lesson, we see that the prefix pre- can indicate doing something to excess or crossing a limit. Adding it creates prespavati, which means to sleep longer than you should have (to oversleep). It also changes the verb from imperfective to perfective, focusing on the completed result.

Could prespavati mean anything else besides oversleeping?

Yes! Besides doing an action to excess, the prefix pre- can also indicate crossing a spatial limit or transitioning. Because of this, prespavati can also mean to sleep over or to spend the night at someone's house. You can always tell which meaning is intended by the context.

Why do we use the present tense kasni right after a past tense verb?

This perfectly mirrors the logical sequence of events. She overslept in the past (prespavala je), and the direct consequence is that she is currently late (kasni). Croatian naturally pairs tenses like this when connecting a past cause to a present effect using tako da (so or therefore).

Why is posao in the accusative case (na posao) instead of the locative?