大象与鲸鱼 陆地上最大，最壮的动物就是大象。海中最大、最重的动物 则是鲸鱼，它也是世界上吃得最多的动物，它每天要吃一吨的食 物。它看起来像鱼，但它实际上是哺乳动物。虽然大象和鲸鱼都 是哺乳动物，它们却大不相同。

Lesson 57
The Elephant and the Whale
The biggest and strongest animal on land
is the elephant. The largest and heaviest
animal in the sea is the whale. It's also the
biggest eater in the world. It eats a ton of
food a day. It looks like a fish, but it is really
a mammal. Although the elephant and the
whale are both mammals, they are indeed
very different.