Mr and Mrs is correct or Mrs and Mr is correct
Mr. and Mrs. (ex. "Hello, Mr. and Mrs. Evans" instead of "Hello, Mrs. and Mr. Evans")
Mr. & Mrs. Smith
In the US it is normally Mr. and Mrs.
Dr. and Mrs. or Mr. and Dr.
Mr and Mrs its just more formal today in society.
I would address it to Mr and Mrs David Keys. For the salutation I would use Dear Mr and Mrs Keys.
"Mr" = "Herr". "Mrs" = "Fru".
It's Atty. and Mrs.
Well, my opinion is Mrs. and Mr. means their married. For example, Mrs. is married to a Mr..
It can be but Mr. and Mrs. Jones or Mr. and Mrs Carl Jones are equally acceptable.
Mr. Bill Mr. Pat Mr. Phil Mrs. Christine Mrs. Joanne Mrs. Evilyn