【简答题】

    As I got into a taxi one afternoon, the driver was very angry about something that had happened to him earlier that day. Here’s how he told the story:
    “One of my passengers left a wallet in my cab this morning. Nearly three hundred dollars in it. I spent more than an hour trying to trace the guy. Finally I found him at his hotel. He took the wallet without a word and glared at me as though I’d meant to steal it.”
    “He didn’t give you a reward?” I asked.
    “Not a cent. But it wasn’t the money I wanted,” he fumbled, then exploded, “If the guy had only said something…”
    Why was the driver so upset? All he wanted was something simple, but even more valuable than money: to be thanked for his efforts. In short, what he wanted, what he needed but did not get, was a little bit of gratitude.
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