class WordTransformer {

    public static String getSimplePast(String verb) {
        if (verb.isEmpty()) {
            return verb;
        }

        String stemmedWord = stemEnglishWord(verb);
        EnglishVerb englishVerb = IRREGULAR_VERBS.get(stemmedWord);

        if (englishVerb != null) {
            return englishVerb.getSimplePast();
        }

        return getRegularVerbPast(verb);
    }

}