The second-hand market is a place where people concentrate their unused items for exchange and trade, and buy and sell second-hand items in the second-hand market at low prices, and some items in the second-hand market are 80% or 90% new, but they are sold for only half of the original price, and thus are very popular, so the second-hand market is a place for many people to dispose of their old things, and the second-hand trading market is also known as the flea market.