This is a hard constraint set because CHUCK is slippery: it can be a name, a verb, a dismissal, a throw, or just a blunt comic sound. That kind of flexibility can help, but in haiku it also creates a trap, because the poem can start reading like a pile of usable meanings instead of one coherent moment. Mick’s “to LEARN life’s rhythm / watch a lean BOUGH, THUMP a tree / SHUCK clams and CHUCK shells” is a strong example of solving that problem. The constraint words are absorbed into physical action, so the final CHUCK feels like the natural end of the motion rather than the required answer word. Across the set, the stronger entries do the same thing: they give the prompt words a working role inside a scene, which is what keeps the word-game pressure from flattening the haiku.