How many days are there in February 2020?

29 days is a leap month, which is added in the lunar calendar to make the average length of the calendar year close to the tropic year. In the lunar calendar, the length of the first lunar month (29.5306 days) is taken as the average value of one month, and a year is 12 months, which is about 10 days and 2 1 hour in the tropical year (365.2422 days). So we should make a leap, three years a month, five years two months, and nineteen years a month.

Leap month is called "national month" after a certain month. For example, the fifth lunar month in 2009 is the ugly May (June 23rd, 2009-July 2nd, 20091). 20 12 lunar April (20 12 May1-20/2 June 18 year), Wu Jianian (20 14 September).