birchbark

例句：

1. 1. The birchbark isa natural insulator, keeping thehouse warm in winter.
   桦树皮是一种天然的绝缘材料，冬天能保持房屋温暖。
2. 2. The birchbarkis used to make furniture and other items.
   桦树皮被用来制作家具和其他物品。
3. 3. The birchbark isalso used as a natural remedy for skinconditions.
   桦树皮也被用作治疗皮肤疾病的自然疗法。