A lot of animals live in the sea. Which animal is your favourite? Now let's have a look at dolphins. Can dolphins talk? Maybe they have mouths but they can't talk with words, they talk with sounds. They show their feelings with sounds.
They make a few sounds above water. They make many more sounds under water. People cannot hear these sounds because they are very, very high. Scientists make tapes of the sounds and study them.
Dolphins like to swim and play together. We call it "a school". They don't study, but they travel together. Dolphins are mammals(哺乳动物), not fish, but they swim together like fish in a school.
Dolphins talk to the other dolphins in the school. They give information. They tell when they are happy or sad or afraid. They say "welcome" when a dolphin comes back to the school. They talk when they play.
Sometimes people catch a dolphin for a large aquarium(水族馆). People can watch the dolphins in a show. Dolphins don't like to be away from their school in an aquarium. They are sad and lonely.
There are many stories about dolphins. They help people. Sometimes they save somebody's life. Dolphins' meat is good, but people don't like to kill them. They say that dolphins bring good luck. Many people believe this.
