Maybe many people know the universe is very big.也许不少人知道宇宙是非常大的。
Some scientists thought theuniverse seems to be rapidly expanding its component galaxies moving ever farther apart.
一些科...
Last week, a friend of mine came to visit me, I felt so surprised, because we lose touch for many years,上周，我的一个朋友拜访我，我觉得很意外，因为我们已经很多年没联系了，
he was my classmate when I ...
