Only when in 1918, happily back to work.
A. the war was over … he went
B. was the war over … did he go
C. the war was over … did he go
D. was the war over … he went
网友回答
A. the war was over … he went
B. was the war over … did he go
(答案→)C. the war was over … did he go
D. was the war over … he went
解析：考查时态及倒装句。语义；只有当1918年战争结束时，他才高兴地回去工作。当only位于句首时，主句采用部分倒装，助动词提前。从句不受影响。结合语境可知本句描述的是过去发生的动作，故主从句都用过去时态。选C。