好题，但好难。文盲凑和交作业。重在参与学习。

In about 70000 to 30000 years ago, a new way of thinking and communication came up  which was so-called learning revoluntion. We have no idea why this happend. but there is a commonly accepted theory that a suden gene mutation had modified how human brain was  connected  which made human to think and communicate in a completely  new way.

夏日最后一朵玫瑰，
孤伶伶地绽放；
她所有的好伙伴，
都黯然地退去；
没有与她心心相惜的花儿，
也没有花蕾在近旁，
来影射她的粉颊，
或叹息她的叹息。