This is the 599th most frequent Croatian word.
nastavi
"Continue."
In this case, 'nastavi' is used to prompt someone to persist in an activity, showing its directive function.
Molim te, nastavi čitati knjigu glasno.
Please, continue reading the book aloud.
This usage demonstrates 'nastavi' as a verb meaning to continue or to keep going in a spatial or abstract sense.
Nastavi dalje, trebamo stići na vrijeme.
Keep going, we need to arrive on time.
Here, 'nastavi' is utilized to instruct proceeding from a previous point of interruption or pause.