例句與造句

1. Railway jacking bridge engineering passing through sand pebble ( gravel ) layer , because it is a complex loose coarse fragment accumulation layer , the roadbed must be reinforced
   摘要鐵路頂橋工程中遇到砂卵（礫）石層時，因砂卵（礫）石層是一種復(fù)雜松散粗碎屑堆積層，因此必須對鐵路路基進行加固。
2. It's difficult to find accumulation layer in a sentence. 用accumulation layer造句挺難的