参考答案:
On the ninth day of the ninth month in the Chinese lunar calendar, people celebrate the Double Ninth Festival. Nine is a yang number (a traditional Chinese spiritual concept) in The Book of Changes, so Double Ninth is called Chongyang.Climbing the mountains is one of the most popular traditions on that day. In September the sky is high and the air is fresh, and climbing the mountains is helpful to keep physical fitness. The tradition of eating double-ninth cakes is associated with climbing the mountains. As a kind of festival foods, the double-ninth cake was first used to celebrate the autumn harvest. Later, it developed into the custom of climbing the mountains and eating double-ninth cakes, which means that our life will become better and better. Because double ninth sounds like longevity (jiujiu in Chinese), the Double Ninth Festival nowadays has been given a new meaning-Seniors' Day.