grauwacke

例句：

1. 1. The riverflows through a landscape of gravel androcks.
   这条河流流经一片砾石和岩石的景观。
2. 2. The old house sitson top of a hill, surrounded bygravel and stones.
   这座旧房子坐落在一座小山上，周围是砾石和石头。
3. 3. The road was paved with gravelto make it easier for people to walk.
   这条路是用砾石铺成的，以便人们更容易行走。