---I heard your grandpa used to be a teacherYes. He was a math teacher .A. on the 19

---I heard your grandpa used to be a teacher.
--- Yes. He was a math teacher .
A. on the 1950s
B. in the 1950s
C. at the 1950’s
D. in 1950’s

A. on the 1950s(答案→)B. in the 1950sC. at the 1950’sD. in 1950’s解析：考察年代表达。年份后面加上s，表示某个年代，故选项CD年代表达错误。表示时间时，on表示在具体某一天，in表示在一个时间范围。年代属于一个时间范围，故用介词in，选B。

你的回答很对

如以上回答内容为低俗、色情、不良、暴力、侵权、涉及违法等信息，可以点下面链接进行举报！

点此我要举报以上问答信息