“Pass the frying pan.”
“You’ve forgotten the magic word,” said Harry irritably.
The effect of this simple sentence on the rest of the family was incredible: Dudley gasped and fell off his chair with a crash that shook the whole kitchen; Mrs. Dursley gave a small scream and clapped her hands to her mouth; Mr. Dursley jumped to his feet, veins throbbing in his temples.

Harry Potter and the Chamber of Secrets - Chapter 1 : The Worst Birthday
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