Quasars, at billions of light-years from Earth the most distant observable objects in the universe, are believed to be the cores of galaxies in an early stage of development.
呵呵，OG的古怪很多。这是一个同位语来的，只不过被倒装了一下，请看正常语序： Quasars, the most distant observable objects in the universeat billions of light-years from Earth, are believed to be the cores of galaxies in an early stage of development. 只所以被倒装，其目的就是为了强调那个排在前面的短语at billions of light-years from Earth，意思是强调Quasars这个东东，真的离俺们地球好远好远－－好多好多billions的光年～～
