dolphins：n.海豚；dolphin的复数；
例：
Dolphins are graceful and efficiently swimmers.
海豚游泳动作敏捷，姿势优美。
相关介绍
Dolphins are also social animals.
海豚也是群居动物。
But scientists say dolphins and humans are very similar in some ways. How?
但是科学家说海豚和人类在某些方面非常相似。是怎样相似的呢？
Why do dolphins help the men?
为什么海豚要帮助人类？
Dolphins and humans are similar in another way: both species make plans for getting things they want.
海豚和人类在另一个方面是相似的：这两个物种都为所想得到的东西制定计划。
In the seas of southern Brazil, for example, dolphins use an intelligent plan to get food.
例如，在巴西南部海域，海豚使用了一种很聪明的计划来获取食物。
