I don't know when he . But when he back I’ll let you know.A. comes ; will comeB. will co

问题补充：

I don know when he . But when he back, I’ll let you know.

A. comes ; will come

B. will come; comes

C. comes;comes

D. will come; will come

答案：

A. comes ; will come

(答案→)B. will come; comes

C. comes;comes

D. will come; will come

解析：第一空填将来时will come ,第二空用comes表示“将来”.