“长羽毛”常见的英文表达有 “have/grow feathers” 。
have feathers:强调拥有羽毛这一状态。例如:Birds have feathers.(鸟有羽毛 。)
grow feathers:侧重于描述羽毛生长这一动态过程。例如:Baby birds start to grow feathers after a few days.(幼鸟几天后开始长羽毛 。)