speed of silting up in harbour

例句：

1. 1.The river has been silt-ing up for years.
   这条河已经淤塞了很多年。
2. 2.The harbor is starting to silt up, which can cause problems.
   港口开始淤塞，这可能会导致问题。
3. 3. To prevent further silt-ing up, we need to improve our waste management system.
   为了阻止进一步的淤塞，我们需要改善我们的废物管理系统。