I don't believe you understand a story until you can tell it simply enough for a child to understand. What follows is a medieval trickster tale which has survived into the modern era in Scandinavian folklore; it is an example of Aarne-Thompson Tale Types #1 and #2, which are often combined in sequence. Medieval versions typically cast Ysengrim the wolf in the leading role here, but I have opted for Bruin the bear as in the modern Scandinavian tellings, which customarily present the story as explaining why bears have such short tails.
Once upon a time in the days when the animals could talk and wishes still came true, there lived a bear named Bruin. Now Bruin loved honey, as all bears do. In fact, the only thing in the world he loved to eat even more than honey was fresh fish. Bruin knew he wasn't the cleverest animal in the woods, but he knew a few tricks to get his paws on his favorite food most of the time.
One day Bruin was out gathering honey one last time before settling down to sleep for the winter, when he came upon his friend Reynard, the fox. Now Reynard was a very cunning fox who always had a trick to play. (In fact, Reynard's tricks were so famous that in France they still call all foxes “Renard” to this day.) That day, Bruin saw that Reynard was carrying two fish. Bruin was jealous.
“How did you get those fish?” asked Bruin.
“I caught them,” said Reynard – which he hadn't.
The truth was that Reynard had been out on the road when a fisherman came by pulling a wagon full of fresh fish. Reynard played dead, and the fisherman, hoping to take him home and make a coat out of his skin, had put him in the wagon with the fish.
But as soon as the fisherman's back was turned, Reynard grabbed two of the fish, jumped out of the wagon, and ran away. Bruin didn't know about Reynard's trick, however, and all he wanted was a nice fish to eat before he went to sleep for the long winter.
Seeing how hungry Bruin looked, Reynard said “I could give you one of them, if you like.” But then a thought crossed his mind – a sneaky, tricky thought, the kind that made the fox smile from ear to ear. “Or,” he said, “I could show you how to catch two more of your very own.”
Bruin's mouth watered. “Would you?” he said. “You know how much I love fresh fish.”
Reynard led bruin to the edge of the lake. Bruin stared at it and couldn't believe he would ever catch anything there – the lake was frozen solid. “Don't worry,” said Reynard with a laugh. “The top of the lake is frozen over, but there are still plenty of fish hiding under the ice.”
Reynard told Bruin to make a hole in the ice to reach the fish, and then had him stick his tail through the hole into the water. Bruin's tail went a long way down, for in those days bears had long, bushy tails. “The water is cold,” said Bruin, “and how is this going to get me any fish?”
“Have you seen how people fish?” asked Reynard. “They drop a string into the water, and the fish bite it. Your tail will be just like that!”
Soon, sure enough, Bruin felt something grab around his tail. “I think I caught one!” he cried.
“Wait just a little longer,” said Reynard, “and you'll have another fish on there – maybe even three!” Bruin waited, even though the water was very cold.
Suddenly, they heard a huntsman approach, blowing his horn, his hounds baying. “We have to get out of here,” cried Bruin.
“Yes, we have to run!” said Reynard, and he sprang up and ran away, laughing all the while.
Bruin tried to follow after, but he was stuck in the ice. What he had felt, and taken for a fish, had been nothing more than the lake freezing back into ice around him. He pulled and he pulled, but he was stuck where he sat. And all the while, the hunter was getting closer and closer. Soon, the hounds were so close Bruin could smell them.
“What will I do if I can't get out of here,” thought Bruin, and one more time he tried to get up. Simply trying to stand didn't work, so he pulled and he pulled, and finally with a sudden RRRRRRIP! he found he had pulled himself free. Then he ran like the wind, back to his den, where the hounds could not follow. But he had left nearly all his tail behind in the ice.
Bruin ran back to his den, where he settled down with a bowl of the honey he had found earlier. Then, at last, he took his winter's long sleep. And, save for the fact that he was left with only a very short tail, he lived happily ever after, and to this day all bears have short tails.