IT has been a long time since you dropped in---- 反义疑问句

题目

IT has been a long time since you dropped in---- 反义疑问句
为何要说 hasn't it 而不说 didn't you

答案

反意疑问句在做时要清楚,最后反问的是什么问题.It has been a long time 是主句,since you dropped in是从句.反义疑问句要根据主句来.这里反问的是主句：难道不是（很长时间了）吗?I don't think these are made of ...