I'd like to add, such as Mr., Dr., Ms., etc. They are all abbreviations for Mr. and Ms., while DDS, DMD, DR, PS, PA, etc. They are all his titles. For example, DR stands for doctor, DDS and DMD stand for doctor, PS and PA stand for his occupation, and PA stands for patient. It means that his work is related to the hospital. In short, it has many meanings. For example, Mr. MICHAEL O 'PAULS Ddspa means that this person is a male doctor, Pauls is his last name, Michael is his first name and O is his middle name. And so on. Because there are many foreigners in my workplace, I know something. When they sign, they seldom write Mr. and Ms., but there are more titles and signatures behind them.