任一给定的服务类型有且只有一个服务实现。

There may exactly be only one service of a given service type.

youdao

你在家庭中所扮演的角色有且只有一个。

The role you have in the family is just that a role.

youdao

要记住，在任何时候，你的竞争对手有且只有一个，那就是你自己。

Remember, at any given moment, you are in competition with one person and one person only – yourself.

youdao

Is there a Nash Equilibrium In which one and only one candidate stands?

有且只有一个,候选人参选是纳什均衡吗

耶鲁公开课 - 博弈论课程节选