Looking on the internet deeply has found these results:

May I know is the most popular phrase on the web.

May I know that 11,550,000 results on the web	May I know 158,500,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
Miss Austen, you may know that I have known you for some considerable time during my visits to Steventon. Mr President Office of the Council, I did not ask you what happened in May or June;I know that already. in May I know the name of that man who just left? I think I may know that driver. You may or may not know that I'm something of a philologist. I may not know that much about geniuses, but I do know when someone's keeping a secret.	May I know what surgery you had? May I know your name, please, Miss? May I know where is the Shaolin Temple? May I know at least the reasons? May I know why Monsieur Sous May I know your name please? May I know your name, sir? May I know the nature of your father's business?

May I know that

11,550,000 results on the web

May I know

158,500,000 results on the web

More popular!

Miss Austen, you may know that I have known you for some considerable time during my visits to Steventon.
Mr President
Office of the Council, I did not ask you what happened in May or June;I know that already.
in
May I know the name of that man who just left?
I think I may know that driver.
You may or may not know that I'm something of a philologist.
I may not know that much about geniuses, but I do know when someone's keeping a secret.