natural angle of repose

例句：

1. 1. The angle of the roof is crucial for determining the natural angle of repose.
   屋顶的角度对于确定自然角的静止角度至关重要。
2. 2. During the construction, the engineers carefully measured and recorded the natural angle of repose to ensure the stability of the structure.
   在建设过程中，工程师们仔细测量并记录了自然角的静止角度，以确保结构的稳定性。
3. 3. The research focused on understanding the natural angle of repose in different materials,which could help optimize their design.
   该研究专注于理解不同材料中自然角的静止角度，这有助于优化其设计。