diff --git a/Pendu/GameEngine.swift b/Pendu/GameEngine.swift
index 219891e8252fd7598ea0b0cb6f88723943db991a..d664baeea49513a75c91388fe5bebeaaddfa5c58 100644
--- a/Pendu/GameEngine.swift
+++ b/Pendu/GameEngine.swift
@@ -25,6 +25,7 @@ class GameEngine: NSObject {
     private var wordToGuess : String = "";
     private var attemptsRemaining : Int = 0;
     private var guessedLetters : [Character] = [];
+    private var lastGuessedLetterTime : Date? = nil;
     private var theme : String = "";
     private var difficulty : String = "";
     private var playerName : String = "";
@@ -92,9 +93,37 @@ class GameEngine: NSObject {
     public func guessLetter(letter: Character) -> Bool {
 
         if wordToGuess.contains(letter) {
-            return true
+            let dateNow = Date();
+            
+            var elapsedTime = 100; // temps au dessus du temps de bonus
+            
+            if(lastGuessedLetterTime != nil) {
+                elapsedTime = Int(dateNow.timeIntervalSince(lastGuessedLetterTime!));
+            }
+             
+            var timeBonusMultiplier = 1;
+            switch difficulty {
+            case "Easy":
+                timeBonusMultiplier = 1;
+            case "Normal":
+                timeBonusMultiplier = 2;
+            case "Hard":
+                timeBonusMultiplier = 3;
+            default:
+                timeBonusMultiplier = 1;
+            }
+            let bonusPoints = (10 * (timeBonusMultiplier))
+            
+            if(elapsedTime < 10) {
+                score += 100 + bonusPoints;
+            } else {
+                score += 100;
+            }
+            lastGuessedLetterTime = Date();
+            return true;
         } else {
-            return false
+            lastGuessedLetterTime = nil;
+            return false;
         }
 
     }