diff --git a/00_hello/hello.rb b/00_hello/hello.rb
index 251797306..d51f4a31c 100644
--- a/00_hello/hello.rb
+++ b/00_hello/hello.rb
@@ -1 +1,7 @@
-#write your code here
+def hello()
+  return "Hello!"
+end
+
+def greet(name)
+  return "Hello, #{name}!"
+end
diff --git a/01_temperature/temperature.rb b/01_temperature/temperature.rb
index 251797306..1bee36fa6 100644
--- a/01_temperature/temperature.rb
+++ b/01_temperature/temperature.rb
@@ -1 +1,7 @@
-#write your code here
+def ftoc(a)
+  return ((a - 32)/1.8).round(2)
+end
+
+def ctof(b)
+  return ((b * 1.8) + 32)
+end
diff --git a/02_calculator/calculator.rb b/02_calculator/calculator.rb
index 251797306..49bd6067c 100644
--- a/02_calculator/calculator.rb
+++ b/02_calculator/calculator.rb
@@ -1 +1,15 @@
-#write your code here
+def add(a,b)
+  return a + b
+end
+
+def subtract(a,b)
+  return a - b
+end
+
+def sum(a)
+  c = 0
+    a.each do |b|
+    c += b
+    end
+  return c
+end
diff --git a/02_calculator/calculator_spec.rb b/02_calculator/calculator_spec.rb
index fef7e9d00..f7017a930 100644
--- a/02_calculator/calculator_spec.rb
+++ b/02_calculator/calculator_spec.rb
@@ -82,7 +82,7 @@
   it "multiplies two numbers"
 
   it "multiplies several numbers"
-  
+
 end
 
 describe "#power" do
diff --git a/03_simon_says/simon_says.rb b/03_simon_says/simon_says.rb
index 251797306..0ecc6a40e 100644
--- a/03_simon_says/simon_says.rb
+++ b/03_simon_says/simon_says.rb
@@ -1 +1,42 @@
 #write your code here
+def echo(a)
+  return a
+end
+
+def shout(a)
+  return(a).upcase!
+end
+
+def repeat(a, b = 0)
+  if b == 0
+    return "#{a} #{a}"
+  else
+    c = []
+    b.times do
+      c << a
+    end
+    return c.join(" ")
+  end
+end
+
+def start_of_word(a, b)
+  return a[0..(b - 1)]
+end
+
+def first_word(a)
+  return a.split(" ")[0]
+end
+
+def titleize(a)
+  skip = ["and", "or", "the", "over"]
+  c = []
+  a.split(" ").each do |b|
+    if skip.include? b
+      c << b
+    else
+    c << b.capitalize!
+    end
+  end
+    c[0] = a.split(" ")[0].capitalize!
+  return c.join(" ")
+end
diff --git a/04_pig_latin/pig_latin.rb b/04_pig_latin/pig_latin.rb
index 251797306..a847abcd3 100644
--- a/04_pig_latin/pig_latin.rb
+++ b/04_pig_latin/pig_latin.rb
@@ -1 +1,30 @@
-#write your code here
+def translate(a)
+
+  vow = ["a", "e", "i", "o", "u", "y"]
+  ay = "ay"
+  phrase = []
+
+  a.split(" ").each do |w|
+    # -- cas "squ" --
+    if  w.index("squ")
+      w = w.split(//).rotate(3)
+      word = w.join("") + ay
+    # -- cas "qu" --
+    elsif w.index("qu")
+      w = w.split(//).rotate(2)
+      word = w.join("") + ay
+    # -- voyelle --
+    elsif vow.include? w[0]
+      word = w + ay
+    # -- consonne rotate jusqu'à voyelle --
+    else
+      w = w.split(//)
+      w.rotate! until vow.include? w[0]
+      word = w.join("") + ay
+    end
+
+      phrase << word
+   end
+
+  return phrase.join(" ")
+end
diff --git a/05_book_titles/book.rb b/05_book_titles/book.rb
index 009f2643e..f8d52711f 100644
--- a/05_book_titles/book.rb
+++ b/05_book_titles/book.rb
@@ -1,3 +1,33 @@
 class Book
-# write your code here
+  attr_accessor :title
+
+  def title=(new)
+    c = []
+    conjunctions = ["and", "but", "for", "nor", "or", "so", "yet"]
+    prepositions = ["over", "in", "of"]
+    articles = ["the", "a", "an"]
+    # new = new.to_s
+    new.split(" ").each do |b|
+      if conjunctions.include? b
+        c << b
+      elsif prepositions.include? b
+        c << b
+      elsif articles.include? b
+        c << b
+      elsif b.length == 1 && b == "i"
+        c << b.upcase!
+      elsif b.is_a? Integer
+        # print b
+        c << b
+      else
+        c << b.capitalize!
+      end
+      @title = c.join(" ")
+    end
+  end
+
 end
+
+
+puts @book = Book.new
+puts @book.title = "I Knew When I was 20"