Genau is real german,formal,how it's in the books.
Thomas: Stop playing with food. Hör auf mit Essen zu spielen!
And "eben" is informal (Umgangssprache,Slang ) to show you agree with someome. I argue with you and you agree and I want to say" you see!!" (I told you so) and in German I would just say "eben!!"