These are endings only for adjectival declansion, OG for genitive masculine singular, after soft consonants it becomes EG (dobrog, vruceg...) OJ is the ending for dativ and locative feminine singular (dobroj, vrucoj..), OM is the noun ending for instrumental both masculine and feminine singular (bratom, sestrom) and adjectival ending for dative and locative masculine singular, after soft consonants it becomes EM (dobrom, vrucem...)