Challenge 2 — Solution

Task: Explain why "hungarian:past definite tense" and "hungarian:food"
produce genuinely different-looking lessons, even though both are
triggered by the exact same L2 prompt shape.

Both prompts follow the identical L2 shape - <language>:<topic> - and
that shape alone doesn't determine which of L4's two sub-formats gets
used. What actually decides it is the CONTENT of the topic itself: L2
explicitly routes to sub-format B whenever the topic names a verb
tense or conjugation pattern, and to sub-format A (the standard
topical shape) otherwise.

"past definite tense" is unambiguously a grammar/tense topic, so it
triggers sub-format B - the lesson opens with a full conjugation grid
and a pattern box laying out the tense's own suffix rules, and only
after that does the familiar six-card dialog grid and 20-word
vocabulary table appear, with the vocabulary specifically showing verbs
in their target-tense form.

"food," by contrast, is an ordinary topic with no grammar/conjugation
angle to it at all, so it uses sub-format A directly - the lesson opens
straight into the six-card dialog grid, followed by the same 20-word
vocabulary table, but with no conjugation grid or pattern box anywhere
in it.

Notes:
- Both sub-formats share real structural DNA (the six dialog cards, the
  20-row vocabulary table, the closing tip-box) - the difference is
  entirely in what's ADDED at the front for a grammar topic, not in the
  underlying lesson shape being replaced wholesale.
- This is a good example of one prompt convention (L2) cleanly routing
  to two different output shapes (L4A/L4B) based on genuinely
  recognizing what kind of topic was actually named, rather than the
  prompt syntax itself carrying that distinction.