using System.Text.RegularExpressions;
using System;
public class Test
{
public static void Main()
{
string pattern = @"\b\w+es\b";
Regex rgx = new Regex(pattern);
string sentence = "Who writes these notes?";
foreach (Match match in rgx.Matches(sentence))
Console.WriteLine("Found '{0}' at position {1}",
match.Value, match.Index);
Console.WriteLine("From index - "+rgx.Matches(sentence)[1]);
}
}
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