A man approaches a woman in a nightclub.
'Can I have your number, sexy?' he asks kissing her hand.
'Have you got a pen?' she asks.
'Yes I do,' the man smiles.
'Well,' the woman replies, 'you'd better get back before the
farmer notices you're missing.'
'Yes I do' is the answer to 'Do you Have a Pen', not 'have you got a pen'. The answer to 'have you got a pen' is Yes I have. I must admit I've heard it used regularly recently, but it is still wrong. It's not even as if it shortens or saves any time, it' exactly the same length.