How many days are there in February 2020?

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

A leap month is called a "national month" after a certain month. For example, the lunar month in 2009 is Ugly May (June 23rd, 2009-July 2nd, 20091). In 20 12, the lunar calendar is April (May 20 12, 21-June 20 12, 18) and Wu Jianian (September 20 14).