"We look forward to your favoring us with an order." Possessive Pronouns with Gerunds Use a possessive pronoun with a gerund, the verb form that functions as a noun. This rule is broken frequently, with many writers using the objective case rather than the possessive case. I didn't like his going ( not him going) to New York without me. Their smiling ( not Them smiling) irritated her. Please forgive our intruding. ( not us intruding)

"We look forward to you favoring us with an order," would be much better.

Such an expression is not acceptable! In fact, no such expression exists. I wouldn't even try to express this. It sounds a bit aggressive.

Total wrong