世仇

例句：

1. 1. The two countries have a long-standing rivalry that has lasted for centuries.
   这两个国家有着长期的敌对关系，这种敌对关系已经持续了几个世纪了。
2. 2. The ancient kingdoms were at war for centuries, with no end in sight.
   古代的王国之间打了几百年的战争，没有结束的迹象。
3. 3. The two families are sworn enemies, with no peace between them.
   这两个家族是誓不两立的敌人，彼此之间没有和平可言。