boundary collocation

例句：

1. 1.The boundary collocation between the two countries has been a source of tension for years.
   两国之间的边界组合多年来一直是一个紧张的源头。
2. 2. The boundary collocation between the two cultures is fascinating and complex.
   两种文化之间的边界组合非常迷人且复杂。
3. 3.The boundary collocation between the two parties has been a point of contention in the negotiations.
   双方之间的边界组合一直是谈判中的一个争议点。