American money is widely used in the world and it works on the metric system. The American government prints money in the following denominations¹： $10， 000； $5，000； $1，000； $500； $100； $50； $10； $5； $2；$1.

　　Very few people see all these bills； twenties， tens fives and ones are the most commonly used. We can find a picture of George Washington on the $ 1 bill， Abraham Lincoln on the $ 5， Alexander Hamilton on the $ 10 and Andrew Jackson on the $ 20. There are also pictures on the back （the White House on the $20， the Treasury² building on the $ 10， the Lincoln Memorial on the $5 and a big " ONE" and the American insignia on the $1）。 However， all paper currency is printed on the same size white paper with green ink， so you have to look carefully before handing someone money and when receiving change. Your best bet is to forget the pictures and concentrate on the large numbers in all four corners on the front and back.

　　American coins are easy to remember. One American dollar is equal to 100 cents or pennies. A half-dollar is 50 cents. All but the penny and the nickel are made of silver. The penny is made of copper³. The nickel is made of a metal called nickel.

　　美国的货币在世界各地广泛使用而且遵循的是公制。美国政府印制的钱币有以下比值：一万元、五千元、一千元、五百元、一百元、五十元、二十元、十元、五元和一元。

　　很少有人见到过所有的这些钱币；二十元、十元、五元和一元是常见的。我们能够看到一元的钞票上有乔治。华盛顿的头像，五元上有亚伯拉罕。林肯；十元上有亚历山大。汉弥尔顿；二十元上有安德鲁。杰克逊。背面上也有图像。（二十元上有白宫，十元上有财政大厦，五元上有林肯纪念堂，一元上有大写的"ONE"和美国的标志）。但是所有的纸币都是用绿墨印在大小相同的纸张上的，所以你在交钱和找零头的时候必须看仔细。最好的办法是忘记那些图像，集中注意正反两面四个角上的数字。

　　美国的硬币很好记。一美元相当于100美分。半美元是50美分。除了一分和五分之外，其他的硬币都是银制的。一分是铜做的，五分是镍做的。