Those little questions we ask at the end of sentences to confirm what we already know are called "tag" questions – because they tag onto the end of a sentence to turn it into a little question at the end.
It could be something like, "You can speak Chinese, can't you," where you get that little confirmation question at the end.
University of Michigan English Professor Anne Curzan says we also get invariant tags, like "You can speak Chinese, right?"
Curzan says the tag "right" shows up in the Oxford English Dictionary in 1939.
"That's more recent than I was expecting," she says. "They say it's a U.S. phenomenon."
But tags can be quirky, Curzan says.
"If you think about the tag question, 'You can speak Chinese, can't you,' the sentence itself is an affirmative sentence. 'You can speak Chinese.' And then when you put the tag question on the end, you make it negative, and by doing that, you have a neutral tag question, where you're just confirming something you think you already know."
Curzan says the way you inflect tag questions can mean different things, as well.
"When you don't reverse the negation, I think many of us read that as expressing skepticism, maybe some condescension, as in 'You know that, do you?' Suddenly, you think the person is doubting whether you actually know that, as opposed to confirming it."
There's been some research that suggests tag questions are a powerless language feature, Curzan says.
"It's something that you're looking for other people to affirm, that it must mean that you're insecure in what you're saying."
And that's where context is really important, Curzan explains.
"It can certainly do that – ask for confirmation from someone – but it can also be powerful. Imagine, for example, saying to a student, 'You're going to turn that in on Tuesday, aren't you?' There's nothing powerless about that tag question."
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