A tree is supplying priceless oxygen, the source of human life for free. Everyone knows water is the only elixir of our life. A bird unknowingly ,by dropping the seeds of the fruits it ate, plants more trees. All the creatures on earth who is considered as having less senses than humans is supporting life on earth. But humans who consider himself superior of all the creatures is not only using the hard work of other creatures, but also notorious in polluting and destroying the earth.