198 1 What is the time period? Please give me some advice!

September 28th 198 1 is from 5pm to 7pm on September 28th, 198 1.

The time of the child is 12- 1 o'clock in the evening, the child, ugly, cloudy, hairy, Chen, Si, noon, Wei, Shen, You, Xu and Hai, two hours backward at a time and two hours at a time, so the unitary time is from 5 to 7 pm.