polar vibrational mode

例句：

1. 1. The polar bears are known for their white fur and powerful jaws.
   北极熊以其白色的皮毛和强大的颚部而闻名。
2. 2. The polar ice cap is the world's largest sheet of frozen water.
   北极冰盖是世界上最大的一片冰冻水域。
3. 3. Polar bears live in the Arctic regions and hunt seals for food.
   北极熊生活在北极地区，以海豹为食。