sS ai_renderWordTypesForLine(S s) {
  new LS out;
  for (S word : uniquify(words2(s))) {
    LS cats = ai_categoriesForWord(word);
    out.add(word + ": " + (empty(cats) ? "unknown" : joinWithComma(map angleBracketCategoryToText(cats))));
  }
  ret lines(out);
}