public void Pinyin_RemoveNumbers_Test()
{
Assert.AreEqual(Pinyin.RemoveNumbersAndUnderscore(""), "");
Assert.AreEqual(Pinyin.RemoveNumbersAndUnderscore("tian1"), "tian");
Assert.AreEqual(Pinyin.RemoveNumbersAndUnderscore("tian1xia4 wei?gong"), "tianxia weigong");
}