英语问题 ____are the days when teachers were looked down upon. a.gone b.go c.to go d.going 选A,WHY____are the days when teachers were looked down upon.a.gone b.goc.to go d.going选A,为什么,并解释这句话的含义

倒装句。
They days (when teachers were looked down upon) are gone.
（）里是days的限制定语。修饰days.
句子主干就是the days are gone.
翻译:教师被看不起的日子已经过去了。

gone are the days 是一去不复返的意思
句子意思为：那些瞧不起老师们的日子已经一去不复返了。
句子想转达的意思是：老师的地位上升了
were looked down upon 是被动语态 意思是老师们被看不起

这个是这样的：
gone是形容词,意思是过去的、遗失了的等
1.过去的
The spring is gone.
春天已经过去了.
2.遗失了的;无可挽回的
It is a gone case.
这句话的意思是：老师被小看（或蔑视)的日子一去不复返了.