They take short cuts!
or
Five. One to change the bulb and eleven to say they could do it faster.
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but I couldn't find any.
or
It takes two. One to change the bulb, and the other to kick the switch.
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It's not a shrub, it's a lemon tree my dear Watson.
or
The bartender offers him a warm smile and says, "For you, no charge".
or