Read and listen to the conversation. Then click one of the 'Hide/Show' buttons. Complete the conversation and then listen and check.
A: Can I have a gin and tonic and two glasses of white wine, please?
B: Sure ... That's £14.50.
A: Thank you.
B: And here's your change. 50p.
A: Thanks. Er ... How much did I give you? I think you've made a mistake!
A: I think you must have made a mistake. I gave you £20, but you've given me change for 15.
B: No, I don't think so.
A: Well, I'm pretty sure I gave you a twenty-pound note.