border contrast

例句：

1. 1. The border betweenChina and India is very important.
   中国和印度之间的边界非常重要。
2. 2. The border patrolsare responsible for maintaining the security of thearea.
   边境巡逻队负责维护该地区的安全。
3. 3.The border between two countries can be asource of tension.
   两个国家之间的边界可能成为紧张的来源。