<p>I see. That's unheard of at my university. </p>
<p>I've never addressed anyone as Mr. or Mrs., but rather Professor or Dr.</p>
<p>I don't consider them as "teachers", they are experts who have done research. Teachers at high schools don't do research and have it published in a scholarly journal. Teachers are certified to teach a certain subject and yet if you ask him/her a question some don't know the material. Professors have extensive knowledge of their subject. </p>
<p>Mea Culpa</p>