my professor shared to us a special lesson that she learned in her life.according to her she learned a lot in this life with observation.most of the people say that the best teacher is experience.when one experience problem or whatever he or she learns from it. should have to be hit by the car while the traffic light is red just to learn that croossing while the light is red is dangerous? bad thing according to her. when you were there during the time that the guy was hit by the car would you do the same just to know that it is really dangerous.