http://web2.uvcs.uvic.ca/elc/StudyZone/330/grammar/pres1.htm


The magician asks the assistant to lie down on the floor with the face up.
He grabs a blanket and hangs it in front of the assistant and shakes it a bit while talking.
In the meantime the assistant turns face down.
The magician then places the blanket over the assistant and makes magical movements, the assistant does a push-up, also lifting one leg.
The assistant moves back to the ground and the magician lifts the blanket slowly, to give the assistant time to turn back on his back.
When the magician removes the blanket, the assistant is already face up.