noun 下载 🔗分享 底绒,绒毛。 The thick, soft undercoat of some mammals, especially those that spend time in the water Examples : "The beaver's thick underfur keeps it warm even in the icy river. " 海狸厚厚的底绒即使在冰冷的河里也能让它保持温暖。 animal body biology nature part 与AI对话词汇游戏阅读练习