As it happens , we had been having a great number of cases of diphtheria in the school to which this child went during that month.
请问在这里使用完成体和完成进行体的区别是什么?
完成进行体更强调事件在那个月里不断发生吗?还是本质区别并不在此?
I had had a great number of cases of diphtheria during that moth.