angle pin

例句：

1. 1. The angle of the roof is crucial for the stability of the structure.
   屋顶的角度对于结构的稳定性至关重要。
2. 2. He used an angle pin to secure the door.
   他用一个角度针来固定门。
3. 3. The carpenter used a square to mark the angle of the wall.
   木匠用一个直角尺来标记墙的角度。