Word in Plural

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp72
{
    class Program
    {
        static void Main(string[] args)
        {
            string word = Console.ReadLine();


            if (word.EndsWith("y"))
            {
                word = word.Substring(0, word.Length - 1);
                word.Remove(word.Length - 1, 1);
                word = word + "ies";
                Console.WriteLine(word);

            }
            else if (word.EndsWith("o") || word.EndsWith("ch") || word.EndsWith("s") || word.EndsWith("sh") || word.EndsWith("z")
                || word.EndsWith("x"))
            {
                word.Remove(word.Length - 1, 1);
                word = word + "es";
                Console.WriteLine(word);
            }
            else
            {
                word.Remove(word.Length - 1, 1);
                word = word + "s";
                Console.WriteLine(word);
            }
        }
    }
}