Question

Mr Green didn’t know ______ last night. A．when does his son come back B．when his son comes

Mr Green didn’t know ______ last night. A．when does his son come back B．when his son comes back C．when his son come home D．when his son came home

Answer 1

D

动词know后跟的是一个宾语从句，要用陈述句的顺序，故A不正确，主句是过去 时，从句要用过去时一种，只有D用的是过去时，故选D。