There are not only big months and small months in a year. There is another exception. February is neither a big moon nor a small moon. ; Large and small months in the solar calendar:; 4, 6, 9, 1 1 refers to 30 days of abortion, 1, 3, 5, 7, 8, 10, 12 refers to 3 months1day, and the average year is 28 days. ; The average solar calendar year is divided into twelve months, the first month is 3 1 day, the second month is 30 days, and the second month is 28 days. The average calendar month is approximately equal to the average length of Wang Shuo's month of 29.5306 days. ; The size of the months in the solar calendar is regular. Before July, a single month was a big month and two months was a small month. After August, two months are big months and a single month is small, so 1 month, March, May, July, August,1month,1February are big months, and April, June, September,1/kloc. ; Extended data:

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Time unit conversion relation:; 1 year = 12 months (flat year and leap year 13 months); 1 quarter =3 months; 1 week =7 days; 1 day =24 hours; 1 hour =60 minutes; 1 min =60 seconds. ; Conversion of ancient time units in China;

(1) A nail is 60 years. ;

(2) 1 month = 30 days; 1 day =2 days = 10 days; 1 Wait =5 days. ;

(3) 1 min = 15 min; 1 =5 minutes (usage in southern Fujian and Guangdong). ;

(4) 1 night =5 more; 1 more =5 points; 1 point =24 minutes. ;

(5) 1 hour =2 hours.