railway subgrade的用法和样例：
例句
- Repair of the railway roadbed is in Sukhumi to Ozzie Muqi La carried out by the railway line.
修复铁路路基的工作是在苏呼米至奥齐姆奇拉铁路线上开展的。 - The harmony of it, the tracker superstructure, the tunnel and bridge structures is the one of the key problems in the railway modernization.
随着高速铁路和快速客货混运技术的发展人们意识到提高铁路路基压实标准，使之与线路上部结构和桥隧建筑物的标准相协调是铁路现代化的关键问题之一。
