When did you start counting nine? What time is it now?

There is a saying in the China lunar calendar called "Jiujiu", which is used to calculate the seasons. The calculation method is to count from the winter solstice (starting from the winter solstice, it is called "cross nine", which means the beginning of cold), and every nine days are called "nine", the first nine days are called "one nine" and the last nine days are called "two nine"

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