Answer:
The structure in the story talks about money and happiness
There was no happiness which change its meaning of the rocking horse winner.
The plot is of a young boy trying to make his family happy, especially his mother, by earning money through gambling in horse races. The themes include the dangers of materialism and greed, as Paul exhausts himself trying to please his mother, who is never satisfied. The characters include Paul (the young boy), as well as his family (his parents and uncle) and the household gardener. The setting is likely 1920s England.
The plot centers around Paul, whose mother doesn't really love him or her other children and who really wants a better life than her circumstances can afford. Paul discovers that he can predict the upcoming winners of horse races by riding a rocking horse at his house. He hides this from his mother but quietly places bets and makes quite a bit of money which he uses to surprise his mother. It's not enough for her, and he works even harder to make her happy through more intense riding. Eventually, his efforts kill him.
Explanation
There are several that could apply. One is that people who rely on money for personal fulfillment will find ultimate disappointment. Paul's mother desires money above all else, which leads her son to his death
Well, a quick look at the characters tells us there's little or no happiness for anyone in this story. Here we go:
Father-- Married to a bitter wife who never has enough--even when she gets more, it doesn't satisfy her. She claims he's unlucky. His son dies.
Mother-- Has everything--house, servants, kids, stables, clothes, and more--but it's not enough. Bitter and discontent because she feels she has no luck, despite the things she has, mentioned above. Her son dies.
Sister-- Has to also sense the throbbing financial needs of the house and the bitterness of her mother. Her brother dies.
Uncle Oscar--Perhaps a little happy, since he did make some significant money on the races; however, he also has to feel some guilt about being somewhat responsible for his nephew's death.
Bassett--The stable boy who gets Paul started on his betting "career" has made a lot of money, so he is certainly happier. However, he, too, must feel some guilt regarding the boy's death.
Paul--Hears the cries of the house and longings of his mother, understands that money is what will make her happy (because that's what she says), then discovers money is not enough. He, of course, dies trying to create more money. He tells his mother he's lucky, and there is apparently some truth to that--for awhile. He may have a moment or two of happiness in his life, like when he anonymously gifts his mother with money, but it doesn't last.
Even the house is not happy--
"And so the house came to be haunted by the unspoken phrase: There must be more money! There must be more money!"