to continue doing sth until it has finished or been completed, even though it is difficult :
Very few of the trainees have stayed the course.
to continue doing sth until it has finished or been completed, even though it is difficult :
Very few of the trainees have stayed the course.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005