What’s the similarity between your uncle and your hands?
They can both do dirty things.
Uncle and Hands Similarity
Explanation
The joke uses the ambiguity of the phrase "dirty things". It plays on the idea that hands can do physically dirty work, and then suggests that one's uncle might be involved in morally dubious actions. It's a bit cheeky and relies on a double entendre.
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i thinks
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i thinks
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i thinks
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i thinks
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i thinks