小牛皮

例句：

1. 1. The shoes are made of genuine leather.
   这些鞋子是用真正的皮革做的。
2. 2.He bought a calfskin wallet for his birthday.
   他生日时买了一个羊皮钱包。
3. 3. The calfskin is soft and warm, making it a popular choice for winter wear.
   羊皮柔软且保暖，是冬季穿着的热门选择。