What this hadith means"Biru abahakum tabirukum abnahakum
Bir= righteousness, doing good, being right
and in the hadeeth it is saying; "Do BIRR to you fathers and your sons will do BIRR to you."
Birru= do Birr, do good, be right to
Abaa-akum= your fathers ("abaa"=fathers) ("kum"= your in plural)
ta-Birr-ukum= (they will do Birr/good/right to you)
abnaa-akum= your sons ( "abnaa"= sons) ("kum"= your in plural)