阅读短文，根据短文内容回答问题。（共10分，每小题2分）
We’ve all heard of mermaids. They are the beautiful half-human, half-fish creatures(生物). They have the head and body of a human and the tail of a fish. We also know that mermaids only exist in fairy tales. But where did all the stories about these creatures come from? If you have ever seen a manatee, then you might have an idea.
Manatees, which are also called sea cows, are mammals(哺乳动物) that live in the sea. Since they are mammals, they have to swim up to the surface to breathe air. Many people believe that the story of the mermaid began with the ancient sailors who saw the manatees putting their heads out of the water to breathe. Because manatees are upright when they do this, it looks like they are standing. If a sailor saw a manatee doing this from far away across the sea, it is possible that the sailor would mistake the manatee for a creature that is half-human, half-fish.
Mermaids are described as having very long hair. This is probably because manatees like to swim up to the surface of the water in areas where there is sea grass. Manatees eat all kinds of plants in the sea, including sea grass. The sea grass around the manatee’s head when they eat could create a picture of long hair.
Manatees also have powerful tails that are very similar to the fish-like tail of a mermaid. The sailors probably watched manatees come up for air and then swim back below the surface, using their paddle-shaped tails. This would explain why the sailors thought mermaids had fish-like tails.
小题1:What are mermaids?
小题2:Where do manatees live?
小题3:Do manatees need to breathe air out of water?
小题4:What do manatees eat?
小题5:Why did the ancient sailors mistake manatees for mermaids?
小题1:They are the beautiful half-human, half-fish creatures.
小题2:In the sea.
小题3:Yes.
小题4:They eat all kinds of plants in the sea.
小题5:When manatees were seen from distance, their heads looked human-like, the sea grass around their heads looked like long hair, and they swam with their paddle-shaped tails.
题目分析：这篇短文主要介绍了传说中的美人鱼有人类的头和身体,一条鱼样的尾巴。许多人认为这实际上是古代水手误把海牛看做了美人鱼。
小题1:根据第一段We’ve all heard of mermaids. They are the beautiful half-human, half-fish creatures(生物).可知美人鱼是什么样子的，故填They are the beautiful half-human, half-fish creatures.
小题2:根据第二段Manatees, which are also called sea cows, are mammals(哺乳动物) that live in the sea. 可知海牛生活在海里，故填In the sea.
小题3:根据第二段Since they are mammals, they have to swim up to the surface to breathe air.可知海牛要到水面呼吸，故填Yes.
小题4:根据第三段Manatees eat all kinds of plants in the sea, including sea grass.可知海牛吃海里的各种植物，故填They eat all kinds of plants in the sea.
小题5:根据第二段If a sailor saw a manatee doing this from far away across the sea, it is possible that the sailor would mistake the manatee for a creature that is half-human,half-fish.第三段This is probably because manatees like to swim up to the surface of the water in areas where there is sea grass. 第四段The sailors probably watched manatees come up for air and then swim back below the surface, using their paddle-shaped tails.描述，故填 manatees were seen from distance, their heads looked human-like, the sea grass around their heads looked like long hair, and they swam with their paddle-shaped tails.