up brush sth up | ˌbrush ˈup on sth
to quickly improve a skill, especially when you have not used it for a time :
I must brush up on my Spanish before I go to Seville.
up brush sth up | ˌbrush ˈup on sth
to quickly improve a skill, especially when you have not used it for a time :
I must brush up on my Spanish before I go to Seville.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005