assertTrue(results.contains("aiueo"));
    }

    public void test_convertWithShi() {
        List<String> results = converter.convert("シ", null);
        assertTrue(results.contains("si"));
        assertTrue(results.contains("shi"));
    }

    public void test_convertWithChi() {
        List<String> results = converter.convert("チ", null);
        assertTrue(results.contains("ti"));