Originally Posted By: PandaBear
Originally Posted By: Volvo_ST1
"What 4 legged animal can jump higher than a house can" is grammatically incorrect with or without "can." The sentence implies that a house can jump, which obviously makes zero sense.
The question should be, "What four-legged animal can jump higher than a house is?"
Nope, that's the main reason why it works, because people tends to misread it as a "horse" rather than a "house", it make grammatical sense, but not logical sense, but works because we missed the spelling in our mind.
It doesn't work on anybody who has a marginal grasp of grammar, for example, small children and people who would be unable to pass an ESL exam. Of course, riddles for children often depend on perceived ambiguity.
My suggestion was obviously not how to formulate a riddle, rather it was how to say the sentence grammatically correct without the perceived ambiguity. I say "perceived," because the original sentence is not ambiguous, but just plain doesn't make sense.