6、Even seemingly insignificant remains can shed interesting light on the history of early man.
shed light on=throw light on=cast light on 解释，说明，揭示
=make a matter clear or understood
-- This information shed light on the problem.
-- Can you shed light on the case of the fire? 你能够解释这次火灾吗?
-- She will shed light on the case of stolen jewels.
Up to now, historians have assumed that calendars came into being with the advent of
agriculture, for then man was faced with a real need to understand something about the
up to now=so far 到目前为止
come into being=come into existence 产生，出现
come into 的用法：
-- come into power 上台
-- come into use 开始使用
be faced with a real need to do sth. 面临着做某事的真正需要
-- We are faced with a real need to learn English well.