[简答题]简述开关量输入摸版的基本组成.

Robert Spring, a 19th century forger (伪造者), did well in his job that he was able to make his living for 15 years by selling false signatures of famous Americans. Spring was born in England in 1813 and arrived in Philadelphia in 1858 to open a bookstore. At first he made some money by selling his small but real collection of early US autographs (亲笔签名). Discovering his ability at copying handwriting, he began to learn the signatures of George Washington and Ben Franklin and writing them on the title pages of old books. To reduce the chance of being discovered, he sent his works to England and Canada for sale.
Forgers have a difficult time selling their products. A forger can’t go to a respectable buyer but must deal with people who don’t have much knowledge in the field. Forgers have many ways to make their works look real. For example, they buy old books to use the aged paper of the title page, and they treat paper and ink with chemicals.
After the Civi
A. There was a greater demand there than in America.
B. There was less chance of being discovered there.
C. Britain was Spring’s birthplace.
D. The prices were higher in England and Canada.