问题补充：
After many years’ hard working, his parents managed to the debts for his education at university.
A. pay for
B. pay back
C. pay off
D. pay out
答案：
A. pay for
B. pay back
(答案→)C. pay off
D. pay out
解析：短语辨析. A.赔偿 B. 偿还 C.付清 D.付出钱.根据题意,辛勤工作多年之后,他的父母设法还清了他上大学的债务.故选C.
