一般情况下是和普通反意疑问句一样,在情态动词上改,比如.
You can play piano, can't you?
He can't go to school today, can he?
但注意下列情况:
1 当陈述部分带有情态动词ought to时,反意疑问部分在英式英语中用ought to 形式,在美式英语中用should形式.例如：
You ought to see the new picture,shouldn't you?
Teachers ought to be honoured,oughtn't they?
2 当陈述部分带有情态动词used to时,反意疑问部分可以用used to形式,也可以用did形式.例如：
She used to live abroad,usedn't she?
There used to be a newsstand in the corner of the street,didn't there?
3 当陈述部分带有情态动词must时,反意疑问部分需视must的含义而定.
a.当must表示“命令或强制”时,反意疑问部分用mustn't.例如：
You must do it by yourself,mustn't you?
b.当must表示“有必要”时,反意疑问句用needn't,例如：
You must see him tonight,meedn't you?
c.当must表示“一定”或“想必”等推测意义时,反意疑问部分不用mustn't,而根据must后的动词形式而定.例如：
He must be crazy to do so,isn't he?
She must have been there for a long time,hasn't she?
They must have stayed at home last might,didn't they?
4 当陈述部分带有need时,反意疑问部分需视need的含义而定.如果need用作情态动词,则反意疑问部分用need形式；如果need用作实义动词,表示“需要”,则反意疑问部分用do形式.例如：
You needn't go there,need you?
She needs to fo there,doesn't she?
Plants need sun to grow,don't they?