1. Bulldozers piled up huge mounds of dirt. 推土机堆起了一个个大土堆。
2. Pits and mounds have significantly different soil properties than other areas in the forest. 与森林中的其他地区相比，坑和土丘的土壤性质有显著的不同。
3. Archaeologists know that mounds such as these are the kinds of geological features that indicate the presence of ancient settlements. 考古学家知道，像这样的土堆是能表明有古代定居点存在的地质特征。
4. The burials actually formed a pattern, the tallest skeletons being found in the mounds, and the heights declining as burials became more distant from the mounds. 墓葬实际上形成了一种模式，在土堆中发现了最高的骨架，随着墓葬距离土堆越远，其高度就越低。
5. The bulldozers piled up huge mounds of dirt. 推土机推起一堆堆泥土。
