People use money 86 food, books, bicycles and hundreds of other things they 87 .When they 88 ,they usually get paid in money. Most of the money used today 89 metal or paper. But in ancient times people often used all kinds of things as money. One of the first kinds of money was shells(贝壳). In ancient China, cloth and knives 90 money. Elephant tusks(象牙),monkey tails(尾巴)and salt were used in some parts of Africa. Rice was also a kind of money used by the ancient people on some islands. Cows and other animals were used as money. too. The first copper(铜)coins 91 China. They were round and had a square(正方的)hole in the center. Different countries have used different metals for their money. Later some countries 92 to make coins of gold and silver(银).But gold, silver and copper were heavy 93 when people needed a lot of coins to buy something expensive. The Chinese were the first 94 paper money. The first paper money didn’t 95 like the paper money we use today.