Group 1 - The narrative revolves around a family meal where the protagonist's grandson tries a traditional Beijing drink called Douzhi, highlighting generational differences in food preferences and experiences [1] - The grandson expresses curiosity about the snacks of the past, indicating a contrast between his current experiences and those of his elders [3][4] - The conversation touches on various traditional snacks, illustrating the cultural significance and nostalgia associated with them [6][8] Group 2 - A story from the protagonist's childhood is recounted, focusing on a teacher's influence on students regarding snack consumption and the social dynamics in the classroom [11][12] - The teacher's efforts to discourage snack consumption lead to a notable change in behavior among students, showcasing the impact of authority figures on children's choices [14][20] - The narrative concludes with a poignant moment about dignity and respect, as a student refuses to accept food due to personal principles, emphasizing moral values over material needs [20][21]