What do you mean by kowtowing at the wedding?

Wedding kowtow is a wedding custom in China traditional culture, which shows respect and gratitude to elders, relatives and friends.

At the wedding, the bride and groom should kowtow to their parents to show their filial piety. Before the groom goes to pick up the bride, he should kneel in front of his parents-in-law, thank them for marrying such a good girl, and promise to take care of the bride in every way in the future; The bride should also kowtow at the same time and thank her parents for their decades of parenting. When the bride changes her mind at the man's house, she must kneel in front of her parents-in-law, indicating that she will be a family in the future. If there are any shortcomings, please give me your advice and forgive me.