1. Teacher. The ancients called the teacher Mr to show respect. This tradition has been used to this day, and many schools and institutions still call teachers Mr.
2. honorifics for intellectuals and adult men with certain status (sometimes for women with status and prestige). For example, a famous scholar or social activist is called "Mr" to show their respect and praise.
3. Someone who used to manage accounts or do paperwork. This kind of person is generally responsible for bookkeeping or word processing, so he is called Mr.
4. In the past, it generally referred to people who read books, read faces, calculate divinations and watch Feng Shui. People in these industries used to be called "gentlemen", probably because their work is mysterious and authoritative and needs people's trust and respect.
The address of Mr. Wang means respect, praise and respect, which may be interpreted differently according to the specific situation. In contemporary society, the title of Mr has gradually faded, but it will still be used in formal occasions or literary works.