Yesterday, when I talked with my friends in English, I found a slightly odd sentence in the conversation.
Me: What is your idea about what restaurant we should go for dinner in this shopping street？
Tom：I think McDonald's is the best choice, isn't it？
In effect, I have never seen the subject of the independent sentence not as the same as the pronoun in tag questions, but I'm not sure whether his tag question is wrong. After all, his usage seems to have some logic…
So, can I use the sentence like his？