Many students are optimistic(乐观)about the next fifty years．In factthey think that the world will be a better place than it is now and our lives will be greatly improved．As a resultpeople will have a higher standard of living and live longer．Howeverother students are worried about the future．They say the world willbecome more crowded．Thereforewe will have even more environmental problems andlive in a world with less energy available．But in my opinionI think we will find ways to solve our problems and everyone will live more happily.