static Map<S, O> ai_standardPhrasesGroupingTree() {
  Collection<S> allPhrases = combinedMechSetsCI(mL(ai_language() + " phrase lists"));
  LL<S> toks = listsWithLengthGreaterThan(1, map javaTokC(allPhrases));
  ret tokCListToGroupingWordTree(toks);
}