road maintenance costs

例句：

1. 1.The cost of road maintenance is a major concern for the government.
   道路维护的成本是政府的主要关注点。
2. 2. The company has been investing heavily in road maintenance to improve safety.
   该公司一直在大力投资于道路维护，以提高安全性。
3. 3. The cost of road maintenance is expected to increase due to increased traffic.
   由于交通量增加，预计道路维护的成本将上升。