Three. One to climb the ladder while the second kicks the ladder out from under her. And the third to say, "I knew that was too high for you dear."
or
Because they only know their ABCs "Anybody But Clinton".
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Bike helmets don't fit hippos
or
Bozo The Clown has real hair on his head.
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The bartender offers him a warm smile and says, "For you, no charge".
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Because he wanted to be on time.
or