It reveals the arrogant, cruel and inhuman aggressive mentality of the Japanese invaders in simple vernacular.
The author describes Gaudi's thoughts and feelings with delicate brushstrokes, which makes the characters lifelike and expresses sympathy for them.
It expresses the author's great sadness about the destruction of Beijing and the damage caused by it through metaphor.
Metaphorically, it shows the mother's meticulous care and love for her children.