Someone asked: chickens, ducks and geese also walk on two legs, why not use two legs to represent them? There are two reasons. First, the biggest feature of chickens, ducks and geese is not legs, but wings, which belong to birds. Second: people did not have two legs at first, but evolved from four legs. Two legs are one of the most important characteristics that distinguish other quadrupeds.
Many children can't tell people apart. If the words on it are also people, it is a person with a crooked neck, which is definitely not acceptable. Children can be taught to distinguish in this way.
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