What's the difference between single happiness and double happiness?

This means that in marriage, both men and women welcome the festival together. Double happiness. Mostly used for weddings and other festive occasions; Happiness belongs to literacy, and Oracle Bone Inscriptions's "happiness" is the word "drum" above and the word "mouth" below. Drum means happiness, and mouth means cheering. The main meaning is happiness, happiness and celebration, especially about marriage.

This means that in marriage, both men and women welcome the festival together. Double happiness. Mostly used for weddings and other festive occasions; Happiness belongs to literacy, and Oracle Bone Inscriptions's "happiness" is the word "drum" above and the word "mouth" below. Drum means happiness, and mouth means cheering. The main meaning is happiness, happiness and celebration, especially about marriage.