using System;
using System.Text.RegularExpressions;

public class Test
{
	public static void Main()
	{
                string[] data = {"TE33", "FR56", "not", "blahblahAJ00blah", "ONetwo34"};

                foreach(string myString in data) {
		    if(Regex.IsMatch(myString, @"^[A-Za-z]{2}.*\d{2}$")) {
                        Console.WriteLine("{0} matches", myString);
                    } else {
                        Console.WriteLine("{0} doesn't match", myString);
                    }
                }
	}
}