阅读下面短文,根据文章大意用所给单词的适当形式填空(未提供单词的,限填一词),使文章意思完整、正确。
The Value of a Dollar
When I was nineteen, I had a job at a local bookstore. One night, a young couple came in and walked here and there looking for a book. They seemed (be) the usual type to give mall (worker) a hard time. When they went to pay the book, the girl was a dollar or two short of (buy) the book she wanted.
She looked disappointed. I had a customer discount card and it was still active. I told the girl (gentle), "Hang on, don't worry, you'll have the money to buy the book." I typed my password.
She gave me a (thank) smile. With a dollar left, she and her boyfriend left the store. I believed that I would never see (they) again.
I don't remember how long it was. they did return later that evening just to bring me beautiful card that said "It's people like you who make the world a better place to live in."
I (move) by the little girl and her boyfriend. In fact, they have also made the world a little brighter.