Popov line

例句：

1. 1. The Popov line is a critical part of the railway system.
   波普洛夫线是铁路系统的关键部分。
2. 2.The Popov line runs through the city center, connecting two major neighborhoods.
   波普洛夫线穿过市中心，连接两个主要街区。
3. 3. The Popov line was constructed to improve transportation efficiency.
   波普洛夫线的建设是为了提高交通效率。