oldersea

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 universe at 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～～