英文：unspoken rule (n.)
說明：unwritten rule (不成文的規定)。
例句：
- A lot of people suspected that there were some unspoken rules in the beauty contest. (許多人懷疑該選美比賽有一些潛規則)
- The competition was not fair because it was following some unspoken rules. (這項競賽不公平，因為它遵循一些潛規則)