We Allegedly about a million years ago we became humans as result of evolution. Then we spent 900 thousand years learning to make and use tools; Again another 90 thousand years getting acquainted with fire and its usefulness; Again 9 thousand years becoming gradually experienced in farming; Again 9 hundred years acquiring the skills in building machines... But in this century, the present hundred years,we've learned flying; Achieved the use of nuclear energe-the ultimate energy we can ever tap, And succeeded in landing on the moon. It's said that we'll eventually be able to retain vitality against aging. We have boundless abilities and potentialities. So let us be blessed.