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 one pound coin
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From an old anti smoking advert

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How things are usually done
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Someone who is not all there / someone with mental issues / someone who may be a bit slow / someone who is an idiot

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doing anything as fast as you can

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Feeling really sick
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Movies, Cinema - e.g. "Want to come to the pictures?"
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God no - e.g. "Gad's no!"
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"I dont believe you!"

 

but not necessarily calling someone a lier, can also be said in a state of shock.