Pentandria

例句：

1. 1. The pentagon is a shape with five sides and five angles.
   五边形是一种具有五个边和五个角的形状。
2. 2. The pentagram represents the five elements of nature: earth, air, fire, water, and spirit.
   五角星代表了自然界的五种元素：地、气、火、水和精神。
3. 3. The pentagon is often used in architecture to create a sense of balance and symmetry.
   五边形常用于建筑中，以创造平衡和对称的感觉。