It is calculated by scientists that human are able to travel at velocity of light,which is to say,E.T.s could visit the earth as long as their evolution progress is 1 million years earlier than the human's.However,there is still no any evidence which can prove that E.T.s have visited our globe so far.Therefore,human is a coincidence of the universe and so-called E.T.does not exist.
保证是自己翻的,没有用金山词霸的句子翻译.