Question

why does he break down in tears after the fire..​

Answer 1

After the fire, he broke down into tears because it suddenly struck him that he was suffering a big loss. He realized that his cat could not be seen anywhere. Then, everything hit him at once − the new school, the fire, and his cat.

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Answer 2

After the fire, he broke down into tears because it suddenly struck him that he was suffering a big loss. He realized that his cat could not be seen anywhere. Then, everything hit him at once − the new school, the fire, and his cat. That was when he broke down and cried.