If one side has one, the other side has to get one. Once launched, they cannot be recalled. When they land, they screw up everything forever.
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One; after reflecting in the twilight on the merit of the previous bulb.
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An impasta
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It takes them a long time to swallow their pride.
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I've been framed!
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Does it have to be a light bulb? I've got this neat candle holder...
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