diff --git a/1-exercises/A-undefined/exercise.js b/1-exercises/A-undefined/exercise.js
index 0acfc78d..e3ee07d5 100644
--- a/1-exercises/A-undefined/exercise.js
+++ b/1-exercises/A-undefined/exercise.js
@@ -10,13 +10,13 @@
 */
 
 // Example 1
-let a;
+let a; // variable a hasn't assigned the value
 console.log(a);
 
 
 // Example 2
 function sayHello() {
-    let message = "Hello";
+    let message = "Hello"; // there is no return value inside the function
 }
 
 let hello = sayHello();
@@ -28,9 +28,9 @@ function sayHelloToUser(user) {
     console.log(`Hello ${user}`);
 }
 
-sayHelloToUser();
+sayHelloToUser(); //there is no argument
 
 
 // Example 4
 let arr = [1,2,3];
-console.log(arr[3]);
+console.log(arr[3]); //index 3 doesn't exit
diff --git a/1-exercises/B-while-loop/exercise.js b/1-exercises/B-while-loop/exercise.js
index b459888f..8ce20116 100644
--- a/1-exercises/B-while-loop/exercise.js
+++ b/1-exercises/B-while-loop/exercise.js
@@ -6,8 +6,16 @@
 */
 
 function evenNumbers(n) {
-    // TODO
-}
+  let arr = [];
+  let counter = 0;
+  let evenNum = 0;
+     while (counter < n) {
+        arr.push(evenNum);
+        evenNum += 2;
+        counter ++;
+    }
+   console.log(arr.join());
+ }
 
 evenNumbers(3); // should output 0,2,4
 evenNumbers(0); // should output nothing
diff --git a/1-exercises/C-while-loop-with-array/exercise.js b/1-exercises/C-while-loop-with-array/exercise.js
index d584cd75..79a1ac80 100644
--- a/1-exercises/C-while-loop-with-array/exercise.js
+++ b/1-exercises/C-while-loop-with-array/exercise.js
@@ -16,8 +16,15 @@ const BIRTHDAYS = [
     "November 15th"
 ];
 
-function findFirstJulyBDay(birthdays) {
-    // TODO
-}
+ function findFirstJulyBDay(birthdays) {
+     let i = 0;
+     while(i < birthdays.length){
+        if (birthdays[i].includes("July")) {
+           return birthdays[i];
+        }
+      i++;
+    }
+ }
 
 console.log(findFirstJulyBDay(BIRTHDAYS)); // should output "July 11th"
+//console.log(BIRTHDAYS[5]);
diff --git a/1-exercises/D-do-while/exercise.js b/1-exercises/D-do-while/exercise.js
index f10d0764..3217be51 100644
--- a/1-exercises/D-do-while/exercise.js
+++ b/1-exercises/D-do-while/exercise.js
@@ -7,9 +7,20 @@
 */
 
 function evenNumbersSum(n) {
-    // TODO
+    let counter = 0;
+    let sum = 0;
+    let evenNum = 0;
+    do {
+        sum += evenNum;
+        evenNum += 2;
+        counter ++;
+
+    } while(counter < n);
+    
+  return sum;
 }
 
 console.log(evenNumbersSum(3)); // should output 6
 console.log(evenNumbersSum(0)); // should output 0
-console.log(evenNumbersSum(10)); // should output 90
\ No newline at end of file
+console.log(evenNumbersSum(10)); // should output 90
+console.log(evenNumbersSum(20));
\ No newline at end of file
diff --git a/1-exercises/E-for-loop/exercise1.js b/1-exercises/E-for-loop/exercise1.js
index db5fac64..63f77dad 100644
--- a/1-exercises/E-for-loop/exercise1.js
+++ b/1-exercises/E-for-loop/exercise1.js
@@ -6,9 +6,8 @@
 
 
 // Change the below code to use a for loop instead of a while loop.
-let i = 0;
-while(i < 26) {
+
+for (let i = 0; i < 26; i++) {
     console.log(String.fromCharCode(97 + i));
-    i++;
 }
 // The output shouldn't change.
diff --git a/1-exercises/E-for-loop/exercise2.js b/1-exercises/E-for-loop/exercise2.js
index 081002b2..38d1f6c4 100644
--- a/1-exercises/E-for-loop/exercise2.js
+++ b/1-exercises/E-for-loop/exercise2.js
@@ -28,6 +28,11 @@ const AGES = [
 
 // TODO - Write for loop code here
 
+for (let i = 0; i < WRITERS.length; i++){
+
+       console.log (`${WRITERS[i]} is ${AGES[i]} years old`);
+}
+
 /*
 The output should look something like this:
 
diff --git a/1-exercises/F-for-of-loop/exercise.js b/1-exercises/F-for-of-loop/exercise.js
index 65585c6a..a732024d 100644
--- a/1-exercises/F-for-of-loop/exercise.js
+++ b/1-exercises/F-for-of-loop/exercise.js
@@ -11,6 +11,14 @@ let tubeStations = [
     "Tottenham Court Road"
 ];
 
+for (let x of tubeStations){
+    console.log(x);
+}
+
 
 // TODO Use a for-of loop to capitalise and output each letter in the string seperately.
 let str = "codeyourfuture";
+
+for (let x of str){
+   console.log(x.toUpperCase());
+}
diff --git a/2-mandatory/1-weather-report.js b/2-mandatory/1-weather-report.js
index dcc2bdb0..a24fb80f 100644
--- a/2-mandatory/1-weather-report.js
+++ b/2-mandatory/1-weather-report.js
@@ -12,7 +12,11 @@
 */
 
 function getTemperatureReport(cities) {
-    // TODO
+   let arr = [];
+   for (let i=0; i<cities.length; i++){
+      arr.push(`The temperature in ${cities[i]} is ${temperatureService(cities[i])} degrees`);
+   }
+   return arr;
 }
 
 
diff --git a/2-mandatory/2-retrying-random-numbers.js b/2-mandatory/2-retrying-random-numbers.js
index 10aab37d..c72ccfd6 100644
--- a/2-mandatory/2-retrying-random-numbers.js
+++ b/2-mandatory/2-retrying-random-numbers.js
@@ -11,6 +11,16 @@ function generateRandomNumber() {
 
 function getRandomNumberGreaterThan50() {
     // TODO - implement using a do-while loop
+    let i = 0;
+    do{
+
+        let randomNum = generateRandomNumber();
+        if (randomNum > 50){
+           return randomNum;
+         }
+       i++; 
+    } while(i < 51)
+
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== */
diff --git a/2-mandatory/3-financial-times.js b/2-mandatory/3-financial-times.js
index 2ce6fb73..342480bf 100644
--- a/2-mandatory/3-financial-times.js
+++ b/2-mandatory/3-financial-times.js
@@ -5,8 +5,14 @@
     Implement the function below, which will return a new array containing only article titles which will fit.
 */
 function potentialHeadlines(allArticleTitles) {
-    // TODO
-}
+    let arr = [];
+    for (let i = 0; i < allArticleTitles.length; i++){
+        if(allArticleTitles[i] <= 65){
+            arr.push(allArticleTitles[i]);
+        }
+      }
+    return arr;
+ }
 
 /*
     The editor of the FT likes short headlines with only a few words!
@@ -23,7 +29,13 @@ function titleWithFewestWords(allArticleTitles) {
     (Hint: remember that you can also loop through the characters of a string if you need to)
 */
 function headlinesWithNumbers(allArticleTitles) {
-    // TODO
+    let arr = [];
+    for (let i = 0; i < allArticleTitles; i++){
+        if(allArticleTitles.includes()){
+
+        }
+      return arr;
+    }
 }
 
 /*
@@ -31,7 +43,7 @@ function headlinesWithNumbers(allArticleTitles) {
     Implement the function below to return this number - rounded to the nearest integer.
 */
 function averageNumberOfCharacters(allArticleTitles) {
-    // TODO
+    
 }
 
 
diff --git a/3-extra/1-factorial.js b/3-extra/1-factorial.js
index 31f8052c..9273789b 100644
--- a/3-extra/1-factorial.js
+++ b/3-extra/1-factorial.js
@@ -9,7 +9,14 @@
 */
 
 function factorial(input) {
-    // TODO
+    if (input === 0 || input === 1){
+        return 1;
+    }
+
+    for (let i = input - 1; i >= 1; i--){
+        input *= i;
+    }
+  return input;
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== */
diff --git a/3-extra/3-fibonacci.js b/3-extra/3-fibonacci.js
index 9ef9aec7..1c384160 100644
--- a/3-extra/3-fibonacci.js
+++ b/3-extra/3-fibonacci.js
@@ -14,7 +14,12 @@
 */
 
 function generateFibonacciSequence(n) {
-    // TODO
+  const fib = [0, 1];
+    
+  for (let i = 2; i < n; i++) {
+    fib[i] = fib[i-1] + fib[i-2];
+  }
+  return fib;
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== */