Sheng Jiang 蒋晟

Exercise 5. Sentence Combining

 A coin is a piece of metal that has a certain weight. It has the mark of the people who issued it. The Lydians were a powerful people in Asia who needed a convenient method of receiving payment for products they produced, so they made the first coins in the seventh century B.C. These primitively made coins were composed of "electrum", a natural composition of gold and silver. Later, the Greeks saw these coins and appreciated their usefulness, and they began to make coins, too. About 100 years later, not only many cities in Greece had coins, but cities all over the mainland of Asia Minor also had them. On one hand, gold coins were the most valuable; on the other hand, silver and copper were also used. The Romans later adopted the idea, carrying it on for 500 years, when the art of coinage declined. In the fifteenth century, the art of coinage was revived not only because there was more metal available, but also because there were many skilled artists to engrave to coins in this period of history. The first coins made in America, in 1752, where not regular in shape. As a result, they were not the same weight. Our society, with its vast numbers of coin-operated machines, could not function without this ancient invention.