Mr.

Some would run away and come to M.R. Singleton, my master, but he would only tell them to go home and behave.

There was no mistaking them, and Arthur gave vent to a whistle of consternation as he deciphered an “M.R.”

I received grandmother's dear letter and M.R.'s kind and affectionate card.

The computer says the radiation count is down to ten M.R. above normal.