Green Ideas
Colourless Green Ideas Sleep Furiously is perhaps the most famous sentence in all of Linguistics, given by Noam Chomsky to demonstrate the difference between syntax and semantics—a perfectly grammatical sentence with no understandable meaning, as Wikipedia describes it. I was reminded of it today when I was listening to the song Aazaadiyaan from the movie Udaan.
Back in 1985, a competition was held at Stanford where participants were asked to provide a paragraph or verse that could give enough context to make this sentence meaningful.