Once a donkey lived in a jungle. There was a mango tree in the jungle. He used to see the tree.
One day his friend monkey was climbing tree by tree and eating mangoes.
The donkey was very sad that he cannot eat the mangoes.
The monkey saw his friend, the donkey.. but he was looking very sad.
So the monkey jumped off the tree.
He asked... why are you so sad, my friend?
Because I cannot eat the mangoes.
Ohhh so that's the problem. Donkeys cannot eat mangoes because they cannot climb trees.