In 1785 the Congress of the United States chose the dollar, which is made up of 100 cents, as the basic unit of money.1785年，美国国会选用美元作为基本的货币单位，一美元分为一百美分。　In the United States, there are five coins in common use: the penny （1 cent）, the nickel （5 cents）, the dime （10 cents）, the quarter （25 cents）,and the half-dollar （50 cents）.在美国，流通中的硬币有五种，一分硬币、五分硬币、十分硬币、二十五分硬币和五十分硬币。　Silver and gold coins were once in common use in the United States. Because silver has become so expensive, the old silver dollar has gone out of circulation. To replace the old silver coin, a new silverless dollar was minted in November of 1971. Gold coins were taken out of circulation many years ago.金银币曾经是美国的流通货币。由于银币的费用太高，老式银币已退出流通。代替老式银币流通的是于1971年11月铸造的不含银的新硬币。金币也在许多年前退出了流通。　If you ever visit the United States, you will probably use only four of the paper bills now in circulation: the one-dollar bill, the five- dollar bill, the ten-dollar bill, and the twenty-dollar bill.

　如果你去美国，也许会使用现在流通中的四种纸币：一元币、五元币、十元币和二十元币。　The largest denomination you will see is the one hundred-dollar bill. However, many people do not like to carry a bill of this size in their pockets. The larger denominations （the five hundred-dollar, one thousand-dollar, five thousand -dollar, and ten thousand-dollar bills） are no longer being printed and are going out of circulation. Nowadays transactions that involve large sums of money are made by checks and fund transfers.你所看到的最大面值是一百元的纸币，可是，许多人不喜欢随身携带这种面额的纸币。更大面额的纸币（五百元纸币、一千元纸币、五千元纸币、一万元纸币）不会再印刷，并逐步退出流通。现在，涉及大金额的交易都是通过支票和资金划拨的方式进行