'How Steel Was Tempered' was a Soviet novel by Nikolay Ostrovsky. The main plot of the novel takes place in the 1920s in the Soviet Union. It tells the story of how a young worker, Alexander Khrushchev, grew up to be an outstanding revolutionary and leader in a difficult environment. The main theme of the novel could be understood from the following aspects: 1. The importance of labor: In the novel, Alexander Khrushchev worked hard in the factory and finally became an excellent worker leader through continuous hard work and persistence. This expressed the author's emphasis on labor and recognition of the value of hard work. 2. Discussion of human nature: Many characters in the novel, including Alexander Khrushchev's father, his good friends, his enemies, etc., all show different personalities and human nature. Through their stories, the author explored the complexity and variety of human nature, including kindness, evil, diligence, laziness and so on. 3. emphasize collectivistic: In the novel, Alexander Khrushchev joined the collective labor in the factory and obtained the qualification to lead the collective through his own efforts and performance. This expressed the author's support and recognition of collectivism, and also emphasized the relationship between individuals and the collective. 4. Exploring the role of revolution and leadership: In the novel, Alexander Khrushchev became a revolutionary and finally became an excellent leader through continuous efforts and persistence. This expressed the author's recognition of the role of revolution and leader, and also emphasized the responsibility and obligation of the leader. How Steel was Tempered was a novel that explored the topics of humanity, collectivism, revolution, and leadership. It was a story about the growth of a young worker, Alexander Khrushchev. It expressed the author's recognition and exploration of the values of labor, humanity, collectivism, and leadership.