to be in a difficult or dangerous situation where you could easily make a mistake :
He was walking a fine line between being funny and being rude.
to be in a difficult or dangerous situation where you could easily make a mistake :
He was walking a fine line between being funny and being rude.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005