find Alphabet in Sentence

string input = "Your sentence here";
string[] sentences = Regex.Split(input, @"(?<=[\.!\?])\s+");
foreach (string sentence in sentences) {
    if (sentence.Contains("o") || sentence.Contains("t"))
          Console.WriteLine(sentence);
}

public void getChars(string strWords)
        {
            char[] chrArrSep={' ',','};
            string[] strArrWords = strWords.Split(chrArrSep,StringSplitOptions.RemoveEmptyEntries);
            foreach (string s in strArrWords)
            {
                if (s.Contains('o'.ToString()) && s.Contains('t'.ToString()))
                {
                    Console.WriteLine(s);
                }
            }
        }

string sentence = "your sentence...";

string[] words = sentence.Split(' ');

foreach (string str in words)
{
    if (str.Contains("o") && str.Contains("t"))
    {
         int indexO = str.IndexOf('o');
         int indexT = str.IndexOf('t');

         if (indexT > indexO)
            Console.WriteLine(str);
    }
}

public string[] getWords(string strWord)
{
    char[] chrCompare={' ',',','-'};

    string[] strWords = strWord.Split(chrArrSep);

    var strFilteredWords = (from Word in strWords.AsEnumerable()
                            where Word.Contains("o") && Word.Contains("t")
                            select Word).ToArray();
    return strFilteredWords; 
}