It broke the law of gravity!
or
Because the chicken was on vacation.
or
I just can't think of one atm.
or
White vans.
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There are footprints in the butter.
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Great food, no atmosphere.
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Because you better duck when he's pissed.
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None, but it takes at least one to sit and pray for the old one to go back on.
or
Two. One to hold the bulb and the other to rotate the planet.
or
A hush puppy.
or