Because "year after year" means "year after year" and "year after year", and Chongyang is a traditional festival in China, which is celebrated in cycles every year, so the answer is circular festival.

Double Ninth Festival refers to the ninth day of the ninth lunar month, which is a traditional folk festival in China. The Book of Changes defines "nine" as yang number, and the two yang numbers of "nine nine" are heavier, so it is called "Chongyang"; It is also called "Double Ninth Festival", because both the date and the month conform to nine. Returning to the truth of 1999, the ancients thought that 1999 Chongyang was an auspicious day.

In ancient times, there were folk customs such as climbing to pray for blessings, enjoying chrysanthemums in autumn, wearing dogwood, offering sacrifices to gods and ancestors, and feasting on the Double Ninth Festival. So far, it has added the connotation of respecting the elderly, feasting on the day of Chongyang, and being grateful for respecting the elderly. Climbing mountains and enjoying autumn and giving thanks and respecting the elderly are two important themes of today's Double Ninth Festival.