Here's why:
* Lack of common words: Many essential parts of speech (like articles, prepositions, conjunctions) don't have common words starting with "k."
* Limited vocabulary: While there are "k" words, the range is limited compared to other letters.
You could try a phrase or a nonsensical sentence:
* "Kites keep knocking." (This is a phrase, not a complete sentence.)
* "King kangaroo kicked." (This is grammatically correct but nonsensical.)
Let me know if you'd like to try a different challenge!