Titles, such as Mr., Mrs., Miss, Dr., Rev., etc., are often avoided by many Friends. Instead Friends tend to address each other by first and last name with no title. In many Quaker communities children address adults by either their first names, or first and last names but with no title, and in many Quaker schools teachers are called by their first names as well. It is conventional for Friends who do not know each other well, who in non-Quaker circles would address each other with a title, to use first name and last name together, rather than to adopt the more familiar first name only. Friends also tend not to use the appellation "sir" or "madam" to refer to someone of whom they do not know the name, instead using the term "Friend". In letter-writing, where others might use the phrase "Dear Sir or Madam", many Quakers would instead write "Dear Friend", and in such letters, rather than finishing "yours faithfully" would finish either "yours in truth" or "yours in friendship".