To feign ignorance; to pretend to be unintelligent or unaware, hoping it may turn to one's advantage

Come on now, don't play dumb. You know exactly what I mean!

Andiamo, via, non fare il finto tonto! Sai benissimo cosa voglio dire

They've been engaged for the past ten years and she wants to get married, but he keeps playing deaf and dumb and won't make up his mind. I don't know how long they can keep this up

Ormai sono fidanzati da dieci anni; lei vuole sposarsi ma lui continua a fare l'indiano e non si decide: non so quanto andranno avanti ancora

I'm talking to you and I know you are listening, so don't play dumb with me

Non far finta di niente! Sto parlando con te e so benissimo che mi stai ascoltando