Translation:You are doing
Better than what? "You are doing" is what I see. It could also be "you do" ... but since we have no further context in this sentence, both of these translations sound a bit too short ... Like, what are you telling me I'm doing?
"You are doing" isn't completely grammatically correct in English. "Doing" is a transitive verb and needs an argument of what is being done, for example "you are doing the shopping". Is "fanya" the same in Swahili? Is "unafanya" a grammatically correct sentence, or does it need to include the thing being done?