Don't I know you?
Read and listen to the conversation. Then click one of the 'Hide/Show' buttons. Complete the conversation and then listen and check.
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A: Excuse me, don't I know you from somewhere?
B: Actually, I don't think so.
A: Weren't you at Gavin's party last week?
B: Not me. I don't know anyone called Gavin.
A: Well, someone who looked just like you was there.
B: Well, that's as maybe, but it certainly wasn't me.
A: I am sorry!