in
to put colour inside a particular area, shape, etc. using coloured pencils, crayons , etc. :
I'll draw a tree and you can colour it in.
in
to put colour inside a particular area, shape, etc. using coloured pencils, crayons , etc. :
I'll draw a tree and you can colour it in.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005