sS ai_parseTree_simplifiedText(PTElement e) {
  e = ai_parseTree_descendToComposite(e);
  if (e instanceof ChoosePart) {
    ai_Reconstructed r = e/ChoosePart.reconstruction;
    WeightedProduction prod = r.production;
    //print("Hint: " + prod.simplificationHint + " in prod: " + sfu(prod));
    if (eq(prod.simplificationHint, "L"))
      ret r.a.text();
    else if (eq(prod.simplificationHint, "R"))
      r.b.text();
    ret e/ChoosePart.word.text();
  }
  null;
}