When someone tells you something, you can react in different ways. Watch the video attached above and pay attention to the expressions the characters use to react to what they say.
Here you can find a summary of all the expressions used:
What you say when you hear…
… something surprising: You’re kidding. / I don’t believe it.
… something interesting: Really?
… some good news: How fantastic! / That’s great news! / What a great idea!
… some bad news: Oh no! / What a pity. / Never mind.