Is this a leap month? What month?

In China's traditional lunar calendar, the leap month is set up to make up for the time difference between the lunar calendar and the period of revolution around the sun. Since the average calendar year of the lunar calendar is about 1 1 day shorter than the tropical year, it is necessary to adjust the synchronization between the lunar calendar and the seasons by adding a leap month every few years.

The setting of lunar leap month follows certain rules, but it will not happen every year, nor will it appear in a certain month. If there is no corresponding gas in a lunar month, the month before this month will be set as leap month.