Introduction to the story:
Little tadpoles hold swimming competitions, and they are all scrambling to sign up. They are all wondering who should be the referee. Suddenly, a rabbit and a hedgehog came to the river. The tadpole said, "Can you be our referee?" Rabbits and hedgehogs are very willing.
The rabbit said, "I raised my gun at this end of the river." Hedgehog, you have to swim to the far end of the river to see who swims first. " The race began, and every tadpole swam forward with all its strength and speed. After a long time, the tadpoles finally reached the finish line, but the hedgehog didn't recognize them. It turns out that after such a long time, tadpoles have become frogs.