pern

例句：

1. 1. The pern is a small, round object that can be used for various purposes.
   这个物品是一个小圆形物体，可以用于各种用途。
2. 2. The pern was designed to be easily portable and durable.
   这个物品被设计成易于携带和耐用。
3. 3. The pern has become a popular item in the market.
   这个物品在市场上变得非常受欢迎。