Because you can see right through them!
or
Should've been called Look Who's Hawking, that's my only criticism.
or
Two. One to do the screwing, and one to hear the confession.
or
Decalfinated
or
Snowflakes.
or
Two — one to change the bulb, and one to write a song about how good the old light bulb was.
or
One; she designs the bulb to crawl up the wall, unscrew the old one, and screw itself in.
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None: A `Real Woman' would have plenty of real men around to do it.
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and the other one says, "That's what I was going to say."
or