How hearing they are and seeing they are these two constructions are used to express ‘amazement’ meaning ‘how well they will hear and how well they will see’ on the Day when they come to Us in the Hereafter. Yet the evildoers an example of a proper noun ‘evildoers’ replacing a third person pronominalisation today that is in this world are in manifest error that is error that is evident therein having been deaf unable to listen to the truth and blind unable to see it. In other words the meaning is O you the one being addressed marvel at how well they will be able to hear and see in the Hereafter after they had been deaf and blind in this world.
