If you have questions about the conjugation of зэка or Russian nouns in general, you can practice and get feedback from a professional tutor.
6 компаньонов, 4 бывших зэка, 3 с судимостью за наркотики.
Six partners, four ex-cons, three with previous drug convictions.
Защитить Клифа от опасного бывшего зэка?
Try to protect Cliff from the dangerous ex-convict?