指事物的,用it：
Something is burnt,isn't it?
指人的用they.
Someone is coming,aren't they?something is wrong with the radio, isn't it/ aren't they? 应该都是正确答案吧？是不是人的是复数， 物既可单也可副啊？错误：something is wrong with the radio, aren't they?正确：something is wrong with the radio, isn't it?