英语反义疑问句主要是一些带有un开头的形容词,在反义从句中是否要变.例子:He is unhappy,(is/isn't

He is unhappy,isn' the?
1 带否定前缀的句子变反义疑问句,疑问部分还是用否定形式.即否定前缀不能视为否定词,其反意疑问句仍用否定形式.
It is impossible, isn't it?
He is not unkind to his classmates, is he?
2 而表示否定意思的词语/组变反义疑问句,疑问部分用肯定形式.比如陈述句含hardly,scarely,barely.never.seldom.little...和半否定词时,反义疑问句用肯定形式.
This meeting is unimportant,isn`t it?
完全可以推广到所有带有un、 dis等开头的单词中去.
http://blog.sina.com.cn/s/blog_48f2f3cb010008jo.html(绝对经典)

如果陈述句中包含有如下的否定或半否定词, 如seldom, hardly, never, rarely,little, few, nowhere, nothing，则简短问句通常用肯定形式。
但如果陈述句中仅包含有否定前缀，则简短问句中用否定形式。否定前缀不能视为否定词，其反意疑问句仍用否定形式。
It is impossible, isn't it?
He is no...

这是无关的...主要看be动词后面是否加not,是才叫否定
可推广..
例:
He was unsuccessful, wasn’t he?
The rules are invariable, aren’t they?
He seldom pays more attention to his pronunciation, does he?
He ha...

un dis 等带否定意思的词,反意不用变
前肯后否
前否后肯

isn't
我觉得只和谓语动词有关系