This is the 945th most frequent Croatian word.
sustavu
"Sustavu" means "system" in English, in the dative or locative case.
The 'sustavu' again denotes location or realm of discussion, showing in what system the changes are considered.
Razmišljamo o promjenama u sustavu upravljanja.
We are considering changes in the management system.
Here, 'sustavu' is in the locative case, indicating location, as it is where the information resides.
Informacije su spremljene u sustavu.
The information is stored in the system.
The word 'sustavu' is in the locative case to indicate the indirect object – into which features were added.