to be certain about sth even though you do not have any direct proof and cannot explain why you are certain :
I know I'm going to fail this exam—I can feel it in my bones.
to be certain about sth even though you do not have any direct proof and cannot explain why you are certain :
I know I'm going to fail this exam—I can feel it in my bones.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005