What is high school?

Upper secondary school refers to ten days from the eleventh to the twentieth of each month.

From Guan Zi Zhou He, a strategist in the Spring and Autumn Period: "There are spring, summer, autumn and winter in the year, and there are middle and upper months in the month." Vernacular explanation: there are four seasons in a year: spring, autumn, winter and summer, and a month is divided into three periods: upper, lower and middle.

The middle pronunciation is xún, which means that the tenth day is ten days (a month is divided into thirty days); Ten years old is ten years old; Ten days can also refer to 12 years. Generally speaking, the 10th anniversary or 30th anniversary refers to a zodiac cycle of 12 years.

Extended data:

The prophase and anaphase of a month refer to 1- 10, 2 1-30 (3 1) respectively.

10 is calculated in days = 10 days, and calculated in years = 12 years, which is a complete zodiac year. It's not necessarily a decimal.

In life, there are many examples of non-decimal: 60 minutes per hour and 60 seconds per minute; 24 hours a day; 7 days a week, 30 days a month; A solar term is 15 days; The time unit of 10 day should be 10 day = 12 year, and Pentecost should be 60 instead of 50.

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