river terrace sand

例句：

1. 1. The river terrace sand is a popular tourist attraction.
   河床沙是一个受欢迎的旅游景点。
2. 2.The sand on the river terrace is soft and easy to walk on.
   河床上的沙质柔软，易于行走。
3. 3.The sand from the river terrace has been used in many construction projects.
   河床沙已被用于许多建设项目。