code: @Nullable
    private String getParticipleSuggestion(String word) {
      if (word.startsWith("ge") && word.endsWith("t")) {
        // strip leading "ge" and replace trailing "t" with "en":
        String baseform = word.substring(2, word.length()-1) + "en";
        try {
          String participle = getParticipleForBaseform(baseform);
          if (participle != null) {
            return participle;
          }
        } catch (IOException e) {
          throw new RuntimeException(e);
        }
      }
      return null;
    }
docs: non-native speakers and cannot be found by just looking for similar words.