Question

【题目】–Did Tom know ________?

--I’m not sure.

A. when does Susan come back B. when Susan comes back

C. when did Susan come back D. when Susan came back

Answer 1

【答案】D

【解析】

试题分析：句意：汤姆知道苏珊什么时候回来？主句是过去式，从句也用过去的某一种时态，从句是疑问句要用陈述语序。故选D。