Which response is more appropriate?

Question

If I encountered a friend in a meeting and he said:"I thought you said you couldn't come to the meeting." Can I response him(1) "Oh, no I can." Or I should say(2) "Oh, yes I can"

I thought what my friend said is not a tag question, and in Chinese, I can say "Oh no, I can" which literally means I didn't say that, and I can come here for the meeting. And I know if the sentence A goes like this "You couldn't come to the meeting, could you?", which is a tag question then the answer should be "Oh, yes I can."

So, which reply is the most appropriate one in this situation?

Answer 1

I think phrase 1) is the idiomatic way to say it, and its meaning is similar to what you thought. In writing, though, I would indicate some kind of pause after "no," because the response really consists of two separate phrases. I like using dashes, but a comma or period could also be appropriate.

Oh, no -- I can.

The "no" is used to contradict what the speaker just said. It (briefly and politely) indicates that you don't believe you did say that (perhaps they misunderstood or misremembered something you did say).

When I say a phrase like this, I find that "oh, no" is unstressed, and "I can" -- the important part of the answer -- is stressed.

If you were to use "yes," that would be seen as confirming what they just said. The "I can" might then be momentarily confusing for them. If you think you did say you couldn't make it, but your schedule changed and you forgot to tell them, you could say something like,

Oh, yes, but my schedule changed. I can make it now.