楼上好多机器翻译的,要不就是用法不对,我跟我老公翻译完了,绝对地道的英语,希望你能够满意:One day, a young guy came to Mr Wang's store bought a gift.The gift's cost price was 18RMB and the market price was 21RMB. But the young guy used a 100RMB bill to buy this gift.Mr Wang didn't have change, so he took the 100RMB bill and asked his neighbor to exchang a 100RMB bill...