Question

【题目】My grandma ______ a song with her friends when I came back.

A. sings B. sang C. is singing D. was singing

Answer 1

【答案】D

【解析】句意：当我回来的时候，我的祖母正和她的朋友一起唱歌。根据when I came back可知此处表示过去某时正在做某事，故用过去进行时，故选D。