Re is an interjection commonly used in the greek language but also used in tha Balkans. It is used in speech to gain someone's attention, add emphasis, insult, or express surprise or astonishment, like the Spanish che.
The word probably comes from μωρέ, the vocative of the ancient Greek μωρός 'dull, sluggish, foolish, stupid'.
re is often accompanied by a slang word but generally speaking you can use it any given sentence.
Re malaka how did you crash the car where you drinking and driving again?