How to convet plural word to singular word from textfile?

Question

using System;

using System.Collections.Generic;

using System.IO;

using System.Linq;

using System.Globalization;

using System.Data;

using System.Data.Entity.Design.PluralizationServices;

namespace Master_Thesis

{

class Program

{

static void Main(string[] args)

{

string filename = "TextFile1.txt";

string inputString = File.ReadAllText(filename);

// Convert to lowercase

inputString = inputString.ToLower();

// Define Special Character

string[] stripChars = { ";", ",", ".", "-", "_", "^", "(", ")", "[", "]",

"0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "\n", "\t", "\r" };

foreach (string character in stripChars)

{

inputString = inputString.Replace(character, "");

}

// Split spaces.............

List<string> wordList = inputString.Split(' ').ToList();

//stopwords.........

string[] stopwords = new string[] { "and", "the", "she", "for", "this", "you", "but" };

foreach (string word in stopwords)

{

while (wordList.Contains(word))

{

wordList.Remove(word);

}

}

// ................

Dictionary<string, int> dictionary = new Dictionary<string, int>();

foreach (string word in wordList)

{

if (word.Length >= 5)

{

if (dictionary.ContainsKey(word))

{

// increment the count.........

dictionary[word]++;

}

else

{

// new word add it to the dictionary with an initial count of 1.....

dictionary[word] = 1;

}

}

}

//how many times a word occurs.......

var sortedDict = (from entry in dictionary orderby entry.Value descending select entry).ToDictionary(pair => pair.Key, pair => pair.Value);

// most frequently occurring words

int count = 1;

Console.WriteLine("---- Most Frequent Terms in the File: " + filename + " ----");

Console.WriteLine();

foreach (KeyValuePair<string, int> pair in sortedDict)

{

Console.WriteLine(count + "\t" + pair.Key + "\t" + pair.Value);

count++;

// top 20 words

if (count > 20)

{

break;

}

}

Console.ReadKey();

}

}

}