【明報專訊】In International English there are two uses of the word "sir" and a third use in Hong Kong English.
The word sir is used instead of the name of an important man. For example: May I help you, sir? / Yes sir. This use is common for a military officer, teacher or employer. It is not capitalised. (The female equivalent is madam or ma'am for short.)
The word sir is also used to show that a person has a knighthood. Titles, such as the word Sir are used as a part of the person's name and is capitalised for this use. (The female equivalent is Dame.)
A holder of a knighthood should properly be addressed as Sir Donald or more formally as Sir Donald Tsang, but never Sir Tsang. The honour is not inherited so only Donald, not the family Tsang receives the title. Sir Donald was convicted on a misconduct charge. Knighthoods are taken back if the person has committed a serious crime. It remains to be seen if the British Crown will revoke his knighthood.
Sometimes Americans are given an honorary knighthood. America is a republic that does not allow royal or noble titles. So Americans will still be addressed as Mr, Mrs &c. even if they are given an honorary knighthood.
In Hong Kong the word sir is used to show respect, just like in International English. However in Hong Kong the word order is reversed and capitalised. It is used with the name. So in Hong Kong a school principal might be referred to as Tom Sir, instead of Sir Tom. This use would be strange elsewhere. No British knighthood is required, just a general position of authority. All forms of the word sir show respect, but the usage is different.
■Audio and full text: link.mingpao.com/15488.htm