static void AbstractDemo()
{
TRex trex = new TRex();
Triceratops triceratops = new Triceratops();
trex.EatFood();
trex.Move();
trex.skinType();
trex.Teeth();
trex.Die();
triceratops.EatFood();
triceratops.Move();
triceratops.Teeth();
triceratops.skinType();
triceratops.Die();
triceratops.sleep();
triceratops.Teeth();
triceratops.skinType();
}