Do you know what snow is?  Or a sled? Downhill?
No, sir.
Well, lie face down on the bed. I'm going to transmit the memory of "snow" to you.
A few moments later, Jonas found himself gripping on a hard surface as soft, cold, tiny feelings peppered his body.
He perceived the bright crystals in the air as snow, and the flat hard surface he was sitting on as sled.
As the sled carried Jonas through the snowfall, he also perceived this as downhill. Jonas enjoyed the moment as he comprehended all the things he had perceived.
Once Jonas reached the bottom of the hill, the motion stopped. Soon, he opened his real eyes and found himself back on the bed with the Giver next to him.