scramble words from a sentence using c#

I tried to make a simple game about word randomization, after I made a simple script from a tutorial I managed to make a random word, such as "words" to "wrdos" but how to make a random word in a sentence? I want to make a sentence "I am a teacher" to "teacher a i am", here is an example of a script that I made in C #, what should I change to be able to randomize a sentence and not scramble a word

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 
 
 [System.Serializable]
 
 public class Word
 
 { 
     public string word;
     [Header("leave empty if you want randomize")]
     public string desiredRandom;
 
     
     
     public string GetString()
     {
         if (!string.IsNullOrEmpty(desiredRandom))
         {
             return desiredRandom;
         }
         string result = word;
 
         result ="";
 
 
         List<char> characters = new List<char>(word.ToCharArray());
         while (characters.Count > 0)
         {
             int indexChar = Random.Range(0, characters.Count -1);
             result += characters[indexChar];
             characters.RemoveAt(indexChar);
                    
         }
     
 
         return result;
 
     }
 
 
 }
 
  
 
 public class WordScramble : MonoBehaviour {
 
     public Word[] words;
 
     [Header("UI Reference")]
 
     public CharObject prefab;
     public Transform container;
     public float space;
     public float lerpSpeed = 5;
 
     List <CharObject> charObjects = new List<CharObject>();
     CharObject firstSelected;
 
     public int currentWord;
     public static WordScramble main;
 
     void Awake ()
     {
         main = this;
     }
 
 
 
     // Use this for initialization
     void Start () {
         ShowScramble(currentWord);
         
     }
     
     // Update is called once per frame
     void Update () {
 
         RepositionObject();
         
     }
 
     void RepositionObject()
     {
         if (charObjects.Count == 0)
         {
             return;
         }
 
         float center = (charObjects.Count - 1) / 2;
         for (int i = 0; i < charObjects.Count; i++)
         {
             charObjects[i].rectTransform.anchoredPosition
                 = Vector2.Lerp(charObjects[i].rectTransform.anchoredPosition,
                 new Vector2((i - center) * space, 0), lerpSpeed * Time.deltaTime);
             charObjects[i].index = i;
         }
 
 
     }
 
     public void ShowScramble()
     {
         ShowScramble(Random.Range(0, words.Length - 1));
     }
 
     //
     public void ShowScramble(int index)
     {
         charObjects.Clear();
         foreach (Transform child in container)
         {
             Destroy(child.gameObject);
         }
 
         if (index > words.Length - 1)
         { 
         Debug.LogError("index out of range between 0-" + (words.Length -1).ToString());
         return;
                     }
         char[] chars = words[index].GetString().ToCharArray();
         foreach (char c in chars)
         {
             CharObject clone = Instantiate(prefab.gameObject).GetComponent<CharObject>();
             clone.transform.SetParent(container);
             charObjects.Add(clone.Init(c));
         }
         currentWord = index;
 
     }
 
     public void Swap(int indexA, int indexB)
     {
         CharObject tmpA = charObjects[indexA];
         charObjects[indexA] = charObjects[indexB];
 
         charObjects[indexB] = tmpA;
 
         charObjects[indexA].transform.SetAsLastSibling();
         charObjects[indexB].transform.SetAsLastSibling();
 
         CheckWord();
 
     }
 
     public void Select(CharObject charObject)
     {
         if (firstSelected)
         {
             Swap(firstSelected.index, charObject.index);
 
             // unselect
             //firstSelected = null;
             firstSelected.Select();
             charObject.Select();
             
         }
         else
         {
 
             firstSelected = charObject; 
         }
     }
 
     public void UnSelect()
     {
         firstSelected = null;
     }
 
     public void CheckWord()
     {
         StartCoroutine(CoCheckWord());
        
         }
 
     IEnumerator CoCheckWord()
     {
         yield return new WaitForSeconds(0.5f);
 
 
         string word = "";
         foreach (CharObject charObject in charObjects)
         {
             word += charObject.character;
         }
 
         if (word == words[currentWord].word)
         {
             currentWord++;
             ShowScramble(currentWord);
             
         }
        
     }
 
 
 
     }

thanks for help