What is the meaning of "sending charcoal in the snow" in Farewell to Relatives?

Giving people charcoal to keep warm in snowy days is a metaphor for giving material or spiritual help and encouragement when others are in urgent need.

The article means "snow": the dilemma faced by soldiers. The article mentioned the crucial moment when the volunteers fought against the enemy. The old Korean mother risked her life to send cakes to the soldiers and give them support and help. Therefore, it is called "sending charcoal in the snow".

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