Dear [mr. smith]:
it would give [me/us] great pleasure to have your presence at a reception in honor of the chinese delegation.
the reception will be held in the [the city hall], on [tuesday, october the fourth]. cocktails will be served promptly at [six] to be followed b dinner at [eight].
[i/we] sincerely hope you can attend. let [me/us] know.
sincerely yours