I was the only one, believe it or not, at the store, who was buying floppies today .

不管你相不相信，我是今天唯一一个去商店里面去买软盘的人。

哈佛公开课 - 计算机科学课程节选

You really need that because if you have only one copy of something, you don't have a backup; so, you can store the one copy separately.

你真的很需要这项发明,因为要是你只有一份的话，你就没有备份;,这样的话，你就可以将副本单独留存。

耶鲁公开课 - 金融市场课程节选