平凡的英雄（人民家书）

Group 1 - The article highlights the stories of ordinary heroes in society, showcasing their selfless acts and contributions to their communities through heartfelt letters [6][9][11][13][19] - It emphasizes the importance of kindness, responsibility, and the impact of individual actions on the lives of others, encouraging readers to reflect on their own roles in fostering goodness [10][12][18][20] Group 2 - The letters reveal personal experiences and challenges faced by individuals, such as the sacrifices made by parents and the dedication of teachers, illustrating the theme of perseverance and love [8][11][14][16] - The narratives also underline the significance of community support and the ripple effect of positive actions, as seen in the efforts of individuals like Zhang Shangming, who has dedicated his life to helping others resolve conflicts [19][20]