I know I am but what are you?
A cocky way to shut someone up and make them sound like a moron.
'I know I am but what are you?' I said. He said he was 'a rockstar' and then asked me to pay him royalties.
'I know I am but what are you?' I asked. He said he was 'a legend' and then said he was going to retire.
'I know I am but what are you?' I said. He said he was 'a superhero' and then fell over.
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