Question

【题目】It's never too old to learn. Mars began to learn English in his ____
A.the fiftieth
B.fiftieth
C.fifty
D.fifties

Answer 1

【答案】D
【解析】句意：学到老活到老。Mars在他50多岁的时候开始学英语。短语in one's+整十的复数，表示在某人几十岁的时候。根据题意，故选D。