I need answer , today is my paper.

Solution:

Address
Date

Dear -------
              Subject: Inability to accept the Invitation

I would like to express my gratitude to the Lion's Club for inviting me as the Chief Guest at a seminar on 'Fundamental Rights of Children'. I only wish I could join you as I am sick of this heat. But I am sorry to say that I shall not be able to get away, as I have already promised to preside over an International Level Seminar. 

Yours Sincerely,
Akshay/Amrita
Child Psychologist

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