Six. One to turn the bulb, one for support, and four to relate to the experience.
or
Only one. They don't like to share the spotlight.
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Seven. One to change it and the other six to sing about how good the old one was.
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A gigolo only screws one person at a time.
or
Two. One to screw it in, and one to stab the other in the back and take all the credit.
or
If Trump gets Alzheimers his IQ will go up.
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Because the sea weed
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When it's full.
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To reduce his carbon footprint.
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Half a worm.
or