Dear John,

I want to take this opportunity to express my sincerest gratitude for all the help you have provided me over the years. Your guidance and support has been instrumental in my success, and it means more to me than words can express. I will never forget all the times you were there for me, offering your expertise and encouragement.

Thank you from the bottom of my heart.

Sincerely, 
[Your Name]
Nome: Giovanni
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