I've to write a Very Polite Letter to the person, I don't know.How to start the letter? He's a male and the subject of the letter is a possible exibition of one artist's paintings.
I've just stuck up with this
Hello FlyingCat, welcome to UsingEnglish!
Why not start by posting up the things you want to say to him, in the order you want to say them?
Then we'll help you with the phrasing.