艰难的经历或教训
I have learned from the school of hard knocks the many reasons for staying.
已经从挫折这所学校里面了解到了许多坚守下来的理由。
His brother never went to college; he educated in the school of hard knocks.
他的兄弟从来没上过大学；他是从实际生活中锻炼出来的。
We all have to go through hard knocks before we get to the good stuff, after all.
毕竟人在成功之前总是得受些打击磨难的。
Likewise resourcefulness that Nelson would come by kids through the school of hard knocks.
John's coach Steve Levin called it just another day at the Big East school of hard knocks.
My formal economic training consisted of sleeping through Econ 101 and 20 years of hard knocks on Wall Street.