This is the 646th most frequent Serbian word.
прву
The Serbian word "прву" means "first" in English (feminine accusative singular form).
The word 'прву' is used here as an ordinal numeral agreeing with the noun 'ствар' (thing) in the singular feminine accusative case, denoting the first item in a sequence.
Прву ствар коју морамо урадити је да разумемо проблем.
The first thing we need to do is to understand the problem.
The word 'прву' describes the bird being referred to, matching the singular feminine accusative case of the noun 'птицу' (bird), indicating the first observed bird in this context.
Видео сам прву птицу како лети низ реку.
I saw the first bird flying down the river.
Within this sentence, 'прву' modifies the noun 'реч' (word) in the singular feminine accusative case, signifying the initial word received or heard.