北极星现在还存在吗?
For all we know,the North Star,our faithful companion,might actully have burned out last January or in 1854 or at any time since the early fourteenth century and news of it just hasn't reached us yet.The best we can say-can ever say- is that it was still burning on this date 680 years ago.
这是我在Bill Bryson 所写的 A Short History of Nearly Everything 中提到的,我现在也摸不到头脑了.谢谢你们的回答.