The man became a famous writer when he was .
A. in his fifty
B. in his fifties
C. in fifty years old
D. in fifties
网友回答
A. in his fifty
(答案→)B. in his fifties
C. in fifty years old
D. in fifties
解析：在某人几十岁的时候，英语中用in one’s +数词的复数形式，句意：这个人当他是50几岁时就变成了一个著名的作家。故选B.