using System;
using System.Text.RegularExpressions;

public class Test
{
	public static void Main()
	{
		Regex rx = new Regex("(?<=^.{10}).*");
        String a = rx.Replace("Hello", "...");
        String b = rx.Replace("Quick brown fox jumps over the lazy dog", "...");
        Console.WriteLine("'{0}'", a);
        Console.WriteLine("'{0}'", b);
	}
}