Nothing is more important than happiness,is it (or)isn't it

问题描述:

Nothing is more important than happiness,is it (or)isn't it
Nothing is more important than happiness,is it?Nothing is more important than happiness,isn't?哪个是对的哦

应该用is it .因为前句中有nothing ,这个词本身就含有否定意义,所以后面反义疑问句应该用肯定
我是英语专业的,