好題，但好難。文盲湊和交作業。重在參與學習。

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.

夏日最後一朵玫瑰，
孤伶伶地綻放；
她所有的好夥伴，
都黯然地退去；
沒有與她心心相惜的花兒，
也沒有花蕾在近旁，
來影射她的粉頰，
或歎息她的歎息。