Four-Digit PINs
ATMs (自动取款机) were created (create) in 1967 by a Scottish man named John Shepherd-Barron, who thought that ___41___ (get) cash should be as easy as buying a chocolate bar. But the ___42___ (difficult) was how to ensure that you were who you said you were. To prevent ___43___ (problem), Shepherd-Barron developed a special type of paper check. It worked like the bank card a person ___44___ (use) today. Each check would cause his cash machine to request a ___45___ (person) identification number, or PIN. Only the account ___46___ (own) knew it. Shepherd-Barron already had a six-digit ID number. It was ___47___ (give) to him by the army. So, he was going to let the machine make the ___48___ (require) of a six-digit PIN from everyone who used it. That ___49___ (probable) would have been the standard. However, his wife disliked it. She believed that six digits were ___50___ (hard) than four to remember. Finally, four became the standard.