1·What's more, the earthworks in both regions are of a similar style, suggesting they were built by the same society.
此外，这两个地区的土方工程风格相似，这表明它们是由同一个社会修建的。
2·Most impressive are the effigy mounds, huge earthworks sculpted into the shapes of birds, animals, and other forms, not found anywhere else in the world in such concentrations.
最令人印象深刻的是肖像冢，成鸟，动物的形状雕刻巨大的土方工程，和其他形式，没有发现在这种浓度世界其他地方。
3·This book, written for general readers but incorporating the most recent research, offers a comprehensive overview of these intriguing earthworks and answers the questions, Who built the mounds?
这本书，一般读者撰写，但最近的研究纳入，提供了这些有趣的土方工程全面介绍和解答的问题，是谁的土堆了吗？
4·Earthworks: two excavators to be used for excavation, two construction methods like single pit excavation and strip excavation to be adopted.
土方工程：采用两台挖机机械挖土，采用单坑开挖和条形开挖二种方案。