Pure Brightness Festival, also known as Tomb-sweeping Day in China, falls on the 4thor 5thof April each year. It was started in the Han Dynasty. On this day, whole families, young and old, with flowers visit the graves of their ancestors to pay their respects. Following the custom, tomb sweepers clean and tidy the graves, decorate them with flowers. They burn paper money made for the dead, set off firecrackers and bow before their ancestors' tombstones. On this day, they don't cook. Only cold food is served. However, tomb sweeping is not the only activity during Pure Brightness Festival. This day is also a time for people to enjoy themselves. Other activities include spring outing, flying kites, planting trees, tasting tea and so on. In April, everything in nature takes on a new look. Trees turn green, flowers come out and the sun shines brightly. So it is a good time to be out to appreciate the beauty of nature. People fly kites not only in the daytime but at night. In the dark, some people fly kites with lanterns, which are called "God's lanterns". They plant trees because young trees which are planted during this period are easy to grow up. And they enjoy tea because the tea produced around the festival is said to have good quality. The word "tomb" probably means the same as the word "  _  " in the passage.
grave tombstone ancestor custom