How to calculate the "nine" and "volt" in the lunar calendar? What are the lunar months?

"Sanjiu" refers to the third nine days from winter to the future, which is about the middle and late period of 1. At this time of winter, the days are short, and the ground absorbs the least solar radiation heat. Therefore, the coldest time of the year generally appears around "March 9" after the winter solstice.

"Three volts" refers to the first, middle and last three volts, which is about mid-July to mid-August. After the summer solstice, but in a day, the day is longer than the night, and the hottest time of the year generally appears in the "dog days" of the summer solstice.

Lunar calendar is called lunar calendar, which is based on the moon, because the moon is also called lunar calendar.

For this reason, the Gregorian calendar became the Gregorian calendar.