We spent many years studying the formation of rocks ,.experiencing many sufferings and even dealth .But our hard work in the end, and we made it.
A. paid off
B. paid back
C. given away
D. came out
网友回答
(答案→)A. paid off
B. paid back
C. given away
D. came out
解析：pay off成功;得到回报。“最后我们的努力得到了回报, 我们成功了”。