### Question:
WordTransformer { public static String wordToPluralGerman(String singular) { if (singular == null) { return ""; } return wordToPluralGermanCaseSensitive(singular.toLowerCase()); }  static String wordToSingular(String pluralForm, Language language); static String wordToSingularEnglish(String pluralForm); static String wordToSingularGerman(String pluralForm); static String wordToSingularGermanCaseSensitive(String lowerCasePluralForm); static List<String> splitGermanCompoundWords(String word); static String wordToPlural(String singular, Language language); static String wordToPluralCaseSensitive(String lowercaseSingular, Language language); static String wordToPluralEnglish(String singular); static String wordToPluralEnglishCaseSensitive(String lowercaseSingular); static String wordToPluralGerman(String singular); static String wordToPluralGermanCaseSensitive(String lowerCaseWord); static String stemGermanWords(String words); static String stemEnglishWords(String words); static String stemWords(String words, Language language); static String stemWord(String word, Language language); static String stemGermanWord(String word); static String stemEnglishWord(String word); static void addStemmingException(String original, String stemmed, Language language); static String getThirdPersonSingular(String verb); static String getSimplePresent(String verb); static String getSimplePast(String verb); static String getPastParticiple(String verb); static EnglishTense getTense(String string, AbstractPosTagger posTagger); static EnglishTense getTense(String string, List<Annotation> annotations); static void main(String[] args);  }### Answer:
@Test public void testWordToPluralGerman() { assertEquals("arten", WordTransformer.wordToPlural("arten", Language.GERMAN)); assertEquals("ketten", WordTransformer.wordToPlural("Kette", Language.GERMAN)); assertEquals("apfelkuchen", WordTransformer.wordToPlural("Apfelkuchen", Language.GERMAN)); assertEquals("eilsendungadressen", WordTransformer.wordToPlural("Eilsendungadresse", Language.GERMAN)); }