static S guessGermanOrEnglish_ngrams(int n, S text) {
  Set<S> set1 = uniqNgrams(n, mechCISet("English words"));
  Set<S> set2 = uniqNgrams(n, mechCISet("Deutsche Wörter"));
  ret ngramScoreBySet(n, text, set1, set2, "english", "german");
}