When I asked an American friend to pass me a screw driver to repair my motorbike, he said with a laugh:
Don't screw it up!
I could not understand why. What that screwdriver was for without using it to screw either up or down.
That was until the motorbike I was trying to repair became a real mess and needed a professional hand.
Why couldn't he just say "don't mess it up" instead.
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