underfold

例句：

1. 1.The book is underfolded in the middle.
   这本书中间是折叠的。
2. 2. She folded her clothes neatly before putting them away.
   她把衣服叠好后放好。
3. 3.The underfold of the dress reveals a beautiful pattern.
   裙子的下摆展示了一个美丽的图案。