To youth who really dedicates to cover the earth with light

Today there are many youth who really dedicates to cover the earth with light. They just don't think about their friends, family or relatives but they think about other people and volunteer, donate and help many poor people. Besides there are youth who just think about themselves which means "Selfish". In our youth age what should we really think about? If we go up to our ancestors, there were many people who sacrificed themselves to develop their nations and to restore the light. If we think about the past I hope we have the solution what we have to do today. There are many famous youth like singers, actors, entertainers showing their talents noticing their each nations. Isn't this a good chance to gather our mind in one? The whole world is now greeting a global era. I'm sure there are many other people who is really doing their best out of view to make the world one like sharing each nation's culture, teaching the country's language etc. The more we effort in behave, our wishes will come true.