"Watermelon Man" joke
There was a farmer who grew watermelons, and every week he would check on his crop, and would find that the local kids had got into his field and eaten as many watermelons as they could.
This went on for some time, and eventually the man got fed up replacing the missing watermelons.
After some thought, he came up with an idea.
He made a sign and placed it in the field; the sign read, "Warning! One of the watermelons in this field has been injected with cyanide!" He feels pleased with himself, thinking that will stop the theft of his crop.
A couple of days later, he returns, and the watermelons are all there; but in the distance, he sees another sign.
He walks over to the sign, and reads, "Now there are two!"
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