tern

例句：

1. 1. The terns are flying high in the sky.
   海鸥们在天空中高飞。
2. 2. The terns were seen diving for fish in the ocean.
   人们看到海鸥在海里潜水捕鱼。
3. 3. The terns are an important indicator of the health of our oceans.
   海鸥是衡量我们海洋健康状况的重要指标。