diff --git a/.DS_Store b/.DS_Store
new file mode 100644
index 0000000..5008ddf
Binary files /dev/null and b/.DS_Store differ
diff --git a/string_manipulation.rb b/string_manipulation.rb
index cf49bd9..e7cba12 100644
--- a/string_manipulation.rb
+++ b/string_manipulation.rb
@@ -1,33 +1,116 @@
-# A method to reverse a string in place.
+# # A method to reverse a string in place.
 def string_reverse(my_string)
-  puts "NOT IMPLEMENTED"
-end
+  index = 0
+  length = my_string.length - 1
 
+  while index < length
+    temp = my_string[index]
+    my_string[index] = my_string[length]
+    my_string[length] = temp
+    index += 1
+    length -= 1
+  end
+  return my_string
+end
+# # ----------------------------------------------------------
+#
 # A method to reverse each word in a sentence, in place.
 def reverse_words(my_words)
-  puts "NOT IMPLEMENTED"
+  # puts "NOT IMPLEMENTED"
+  index = 0 # this is for looping over org string
+  length = my_words.length - 1
+  temp = ""
+
+  i = 0
+
+  while index <= length
+    if my_words[index] != " "
+      temp << my_words[index]
+    end
+
+    if my_words[index] == " " || index == length
+      l = temp.length - 1
+
+      while 0 <= l
+        my_words[i] = temp[l]
+        i += 1
+        l -= 1
+      end
+      i += 1
+
+      temp = ""
+    end
+    index += 1
+  end
 end
 
+# ----------------------------------------------------------
+
 # A method to reverse the words in a sentence, in place.
 def reverse_sentence(my_sentence)
+
   puts "NOT IMPLEMENTED"
+  i = 0
+    j = my_sentence.length - 1
+    while i < j
+      temp = my_sentence[i]
+      my_sentence[i] = my_sentence[j]
+      my_sentence[j] = temp
+      i += 1
+      j -= 1
+    end
+    b = 0
+    l = my_sentence.length - 1
+    while b < l
+      i = b
+      until my_sentence[b] == " " || b > l
+        b += 1
+      end
+      j = b - 1
+      while i < j
+        temp = my_sentence[i]
+        my_sentence[i] = my_sentence[j]
+        my_sentence[j] = temp
+        i += 1
+        j -= 1
+      end
+        b += 1
+    end
+    return my_sentence
 end
 
+
 # A method to check if the input string is a palindrome.
 # Return true if the string is a palindrome. Return false otherwise.
 def palindrome_check(my_phrase)
-  puts "NOT IMPLEMENTED"
+  # puts "NOT IMPLEMENTED"
+
+  index = 0
+  length = my_phrase.length - 1
+
+  while index < length
+    if my_phrase[index] != my_phrase[length]
+      return false
+    end
+    index += 1
+    length -= 1
+  end
   return true
 end
 
+
+# ----------------------------------------------------------
+
 # A method that updates the string by replacing consecutive repeating characters
 # with a number representing the frequency. The replacement is done only if the
 # string length will get reduced by the process.
 def encode_repeating(my_string)
   puts "NOT IMPLEMENTED"
+
+
 end
 
-### ---- END OF METHODS
+## ---- END OF METHODS
 puts "Test 1: reverse a string"
 my_string = "Lovelace"
 puts "Original string: #{my_string}"
@@ -39,6 +122,7 @@ def encode_repeating(my_string)
   puts "BUG! The reversed string should be '#{reversed_string}' and not '#{my_string}'"
 end
 
+
 puts "Test 2: reversed words"
 my_words = "I can be an  engineer"
 puts "Original: #{my_words}"
@@ -50,6 +134,7 @@ def encode_repeating(my_string)
   puts "BUG! The reversed words should be '#{reversed_words}' and not '#{my_words}'"
 end
 
+
 puts "Test 3: reversed sentence"
 sentence = "Yoda  is   awesome"
 puts "Original: #{sentence}"
@@ -61,6 +146,7 @@ def encode_repeating(my_string)
   puts "BUG! The reversed sentence should be '#{reversed_sentence}' and not '#{sentence}'"
 end
 
+
 puts "Test 4: Palindrome check"
 phrase = "madam"
 puts "BUG: madam is a palindrome and should return true" if palindrome_check(phrase) != true
@@ -71,7 +157,8 @@ def encode_repeating(my_string)
 # puts "BUG: 'nurses run' is a palindrome and should return true" if palindrome_check(phrase) != true
 puts "Palindrome test complete."
 
-# Optional Question #5
+
+# #Optional Question #5
 # puts "Test 5: Encode test"
 # test1 = "aaabbbbbcccc"
 # encode_repeating(test1)