By reading the above passage, talk about the changes of middle-aged and young people.

Yuetu changed from a lively and lovely boy with a purple round face and a small felt hat to a red-eyed, grayish-yellow and wrinkled stone statue. From a lively, energetic, intelligent, enthusiastic, well-informed and eloquent rural teenager, he has become a "puppet" who is hardworking and simple, but has a hard life, is insensitive and ignorant.

It is through the change of leap soil that the author reflects the social reality that under the double oppression of imperialism and feudalism after the Revolution of 1911, the vast rural areas are increasingly bankrupt and farmers' lives are increasingly difficult. In other words, the change of young leap soil is the inevitable result of the changes of the times and countries.