used to introduce extra information and emphasize what you are saying :
He has two big houses in this country, not to mention his villa in France.
used to introduce extra information and emphasize what you are saying :
He has two big houses in this country, not to mention his villa in France.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005