"A sweep of gold, two silver, three cornucopia. There is a treasure in the cornucopia that children and grandchildren don't need. " How to understand?

In the old society, every household would do a general cleaning on the 24th of the twelfth lunar month to create a brand-new environment for the new year. This is the so-called "sweeping the year", because "dust" and "Chen" are homophonic, and sweeping away dust means sweeping away all "bad luck" and "good luck", which reflects people's desire for good luck and good luck. As this nursery rhyme says, "Sweep the cornucopia of gold and silver." . There is a treasure in the cornucopia that children and grandchildren don't need. "