( saying ) when conditions or progress become difficult (strong and determined people work even harder to succeed)
WHEN THE GOING GETS TOUGH (THE TOUGH GET GOING)
Meaning of WHEN THE GOING GETS TOUGH (THE TOUGH GET GOING) in English
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005