Ostrovsky famously said: Life is a person's most precious thing, and this life belongs to everyone only once. A person's life should be spent like this: when recalling the past, he will not regret because he has wasted his life, nor will he be ashamed because he has accomplished nothing in the past; On his deathbed, he can say, "All my life and energy have been devoted to the most magnificent cause in the world-the struggle for the liberation of mankind."