The rule
Question tags are the tiny questions English speakers add to the end of sentences to invite agreement or keep a conversation going. French has n'est-ce pas ? and non ? — but English has dozens of variations, and using them makes you sound dramatically more natural.
"Great conference, isn't it?"
Super conférence, n'est-ce pas ?
→ Positive statement + negative tag. The most common pattern.
"You don't work in sales, do you?"
Tu ne travailles pas dans la vente, si ?
→ Negative statement + positive tag. You think the answer is no but you're checking.
"The food's amazing, isn't it?"
La nourriture est incroyable, non ?
→ Perfect small talk opener. You're not really asking — you're starting a conversation.
The pattern
Positive sentence → negative tag: "It's warm, isn't it?"
Negative sentence → positive tag: "You haven't been here before, have you?"
The tag always uses the same auxiliary verb as the main sentence (is/isn't, do/don't, have/haven't, can/can't).
Common mistake
French speakers often use "no?" or "isn't it?" for everything. But the tag must match the sentence: "You came yesterday, didn't you?" — not "isn't it?". The auxiliary changes with each sentence.