Question

"What a pest you are ,brother!" He exclaimed why has the listener been called a pest?

Answer 1

Ali was constantly pestering the postmaster to check if he had received any letter from his daughter Miriam.( Pestering wouldnt be the right word )
But,since there had been no letter, the postmaster yelled at Ali and called him a pest.
Pest usually refer to rats and mosquitoes who keep constantly disturbing the routine.
But here,Ali was just inquiring.

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