diff --git a/src/arrays.js b/src/arrays.js
index 822c49b7..0314b284 100644
--- a/src/arrays.js
+++ b/src/arrays.js
@@ -1,62 +1,50 @@
 const getNthElement = (index, array) => {
-  // your code here
+  return array[index % array.length];
 };
 
-const arrayToCSVString = array => {
-  // your code here
-};
+const arrayToCSVString = array => array.toString();
 
-const csvStringToArray = string => {
-  // your code here
-};
+const csvStringToArray = string => string.split(",");
 
 const addToArray = (element, array) => {
-  // your code here
+  array.push(element);
 };
 
-const addToArray2 = (element, array) => {
-  // your code here
-};
+const addToArray2 = (element, array) => array.concat(element);
 
-const removeNthElement = (index, array) => {
-  // your code here
-};
+const removeNthElement = (index, array) => array.splice(index, 1);
 
-const numbersToStrings = numbers => {
-  // your code here
-};
+const numbersToStrings = numbers => numbers.map(String);
 
-const uppercaseWordsInArray = strings => {
-  // your code here
-};
+const uppercaseWordsInArray = strings => strings.map(a => a.toUpperCase());
 
-const reverseWordsInArray = strings => {
-  // your code here
-};
+const reverseWordsInArray = strings =>
+  strings.map(word => {
+    return word
+      .split("")
+      .reverse()
+      .join("");
+  });
 
-const onlyEven = numbers => {
-  // your code here
-};
+const onlyEven = numbers => numbers.filter(number => number % 2 === 0);
 
-const removeNthElement2 = (index, array) => {
-  // your code here
-};
+const removeNthElement2 = (index, array) =>
+  array.reduce((result, elem, i) => {
+    if (i !== index) result.push(elem);
+    return result;
+  }, []);
 
-const elementsStartingWithAVowel = strings => {
-  // your code here
-};
+const elementsStartingWithAVowel = strings =>
+  strings.filter(str => /^[aeiouAEIOU]/i.test(str));
 
-const removeSpaces = string => {
-  // your code here
-};
+const removeSpaces = string => string.replace(/\s/g, "");
 
-const sumNumbers = numbers => {
-  // your code here
-};
+const sumNumbers = numbers => numbers.reduce((a, b) => a + b);
 
-const sortByLastLetter = strings => {
-  // your code here
-};
+const sortByLastLetter = strings =>
+  strings.sort(
+    (a, b) => a.charCodeAt(a.length - 1) - b.charCodeAt(b.length - 1)
+  );
 
 module.exports = {
   getNthElement,
diff --git a/src/booleans.js b/src/booleans.js
index 9def206c..9594c7aa 100644
--- a/src/booleans.js
+++ b/src/booleans.js
@@ -1,62 +1,36 @@
-const negate = a => {
-  // your code here
-};
+const negate = a => !a;
 
-const both = (a, b) => {
-  // your code here
-};
+const both = (a, b) => a && b;
 
-const either = (a, b) => {
-  // your code here
-};
+const either = (a, b) => a || b;
 
-const none = (a, b) => {
-  // your code here
-};
+const none = (a, b) => !a && !b;
 
 const one = (a, b) => {
-  // your code here
+  if (a && !b) return true;
+  if (!a && b) return true;
+  return false;
 };
 
-const truthiness = a => {
-  // your code here
-};
+const truthiness = a => Boolean(a);
 
-const isEqual = (a, b) => {
-  // your code here
-};
+const isEqual = (a, b) => a === b;
 
-const isGreaterThan = (a, b) => {
-  // your code here
-};
+const isGreaterThan = (a, b) => a > b;
 
-const isLessThanOrEqualTo = (a, b) => {
-  // your code here
-};
+const isLessThanOrEqualTo = (a, b) => a <= b;
 
-const isOdd = a => {
-  // your code here
-};
+const isOdd = a => !(a % 2 === 0);
 
-const isEven = a => {
-  // your code here
-};
+const isEven = a => a % 2 === 0;
 
-const isSquare = a => {
-  // your code here
-};
+const isSquare = a => Math.sqrt(a) % 1 === 0;
 
-const startsWith = (char, string) => {
-  // your code here
-};
+const startsWith = (char, string) => string.startsWith(char);
 
-const containsVowels = string => {
-  // your code here
-};
+const containsVowels = string => Boolean(string.match(/[aeiou]/gi));
 
-const isLowerCase = string => {
-  // your code here
-};
+const isLowerCase = string => string === string.toLowerCase();
 
 module.exports = {
   negate,
diff --git a/src/numbers.js b/src/numbers.js
index 028675f9..41fd147d 100644
--- a/src/numbers.js
+++ b/src/numbers.js
@@ -1,46 +1,24 @@
-const add = (a, b) => {
-  // your code here
-};
+const add = (a, b) => a + b;
 
-const subtract = (a, b) => {
-  // your code here
-};
+const subtract = (a, b) => a - b;
 
-const multiply = (a, b) => {
-  // your code here
-};
+const multiply = (a, b) => a * b;
 
-const divide = (a, b) => {
-  // your code here
-};
+const divide = (a, b) => a / b;
 
-const power = (a, b) => {
-  // your code here
-};
+const power = (a, b) => a ** b;
 
-const round = a => {
-  // your code here
-};
+const round = a => Math.round(a);
 
-const roundUp = a => {
-  // your code here
-};
+const roundUp = a => Math.ceil(a);
 
-const roundDown = a => {
-  // your code here
-};
+const roundDown = a => Math.floor(a);
 
-const absolute = a => {
-  // your code here
-};
+const absolute = a => Math.abs(a);
 
-const quotient = (a, b) => {
-  // your code here
-};
+const quotient = (a, b) => Math.trunc(a / b);
 
-const remainder = (a, b) => {
-  // your code here
-};
+const remainder = (a, b) => a % b;
 
 module.exports = {
   add,
diff --git a/src/objects.js b/src/objects.js
index 906eef8f..bc5d8dc2 100644
--- a/src/objects.js
+++ b/src/objects.js
@@ -1,41 +1,39 @@
 const createPerson = (name, age) => {
-  // your code here
+  return {
+    name,
+    age
+  };
 };
 
-const getName = object => {
-  // your code here
-};
+const getName = object => object.name;
 
-const getProperty = (property, object) => {
-  // your code here
-};
+const getProperty = (property, object) => object[property];
 
-const hasProperty = (property, object) => {
-  // your code here
-};
+const hasProperty = (property, object) => property in object;
 
-const isOver65 = person => {
-  // your code here
-};
+const isOver65 = person => person.age > 65;
 
-const getAges = people => {
-  // your code here
-};
+const getAges = people => people.map(person => person.age);
 
-const findByName = (name, people) => {
-  // your code here
-};
+const findByName = (name, people) =>
+  people.filter(person => person.name === name)[0];
 
-const findHondas = cars => {
-  // your code here
-};
+const findHondas = cars => cars.filter(car => car.manufacturer === "Honda");
 
 const averageAge = people => {
-  // your code here
+  const ages = people.map(person => person.age);
+  const average = ages.reduce((a, b) => a + b);
+  return average / ages.length;
 };
 
 const createTalkingPerson = (name, age) => {
-  // your code here
+  const person = {
+    name,
+    age,
+    introduce: personname =>
+      `Hi ${personname}, my name is ${name} and I am ${age}!`
+  };
+  return person;
 };
 
 module.exports = {
diff --git a/src/strings.js b/src/strings.js
index d3caabd8..a10ead54 100644
--- a/src/strings.js
+++ b/src/strings.js
@@ -1,26 +1,14 @@
-const sayHello = string => {
-  // your code here
-};
+const sayHello = string => `Hello, ${string}!`;
 
-const uppercase = string => {
-  // your code here
-};
+const uppercase = string => string.toUpperCase();
 
-const lowercase = string => {
-  // your code here
-};
+const lowercase = string => string.toLowerCase();
 
-const countCharacters = string => {
-  // your code here
-};
+const countCharacters = string => string.length;
 
-const firstCharacter = string => {
-  // your code here
-};
+const firstCharacter = string => string.charAt(0);
 
-const firstCharacters = (string, n) => {
-  // your code here
-};
+const firstCharacters = (string, n) => string.substring(0, n);
 
 module.exports = {
   sayHello,
diff --git a/test/arrays.test.js b/test/arrays.test.js
index d8723452..beb8dee0 100644
--- a/test/arrays.test.js
+++ b/test/arrays.test.js
@@ -19,34 +19,34 @@ const {
 describe("getNthElement", () => {
   const array = ["cat", "dog", "elephant", "fox"];
 
-  xit("returns the element at the given position", () => {
+  it("returns the element at the given position", () => {
     expect(getNthElement(0, array)).toEqual("cat");
     expect(getNthElement(2, array)).toEqual("elephant");
     expect(getNthElement(3, array)).toEqual("fox");
   });
 
-  xit("if n is greater than the number of elements, it cycles back to the start", () => {
+  it("if n is greater than the number of elements, it cycles back to the start", () => {
     expect(getNthElement(4, array)).toEqual("cat");
     expect(getNthElement(5, array)).toEqual("dog");
   });
 });
 
 describe("arrayToCSVString", () => {
-  xit("returns the array elements as a comma-seperated string", () => {
+  it("returns the array elements as a comma-seperated string", () => {
     expect(arrayToCSVString(["a", "b", "c", "d"])).toEqual("a,b,c,d");
     expect(arrayToCSVString([1, 2, 3, 4, 5])).toEqual("1,2,3,4,5");
   });
 });
 
 describe("csvStringToArray", () => {
-  xit("converts the csv string as an array", () => {
+  it("converts the csv string as an array", () => {
     expect(csvStringToArray("a,b,c,d")).toEqual(["a", "b", "c", "d"]);
     expect(csvStringToArray("1,2,3,4,5")).toEqual(["1", "2", "3", "4", "5"]);
   });
 });
 
 describe("addToArray", () => {
-  xit("adds the item to the end of the array", () => {
+  it("adds the item to the end of the array", () => {
     const array = [];
     const array2 = [1, 2, 3];
 
@@ -59,7 +59,7 @@ describe("addToArray", () => {
 });
 
 describe("addToArray2", () => {
-  xit("returns a new array with the value appended", () => {
+  it("returns a new array with the value appended", () => {
     const array = ["a", "b", "c"];
     const array2 = [1, 2, 3];
 
@@ -72,7 +72,7 @@ describe("addToArray2", () => {
 });
 
 describe("removeNthElement", () => {
-  xit("removes the element at position n", () => {
+  it("removes the element at position n", () => {
     const array = ["ant", "bison", "cockerel", "duck", "elephant"];
     removeNthElement(2, array);
     expect(array).toEqual(["ant", "bison", "duck", "elephant"]);
@@ -80,13 +80,13 @@ describe("removeNthElement", () => {
 });
 
 describe("numbersToStrings", () => {
-  xit("converts every number in the array to a string", () => {
+  it("converts every number in the array to a string", () => {
     expect(numbersToStrings([1, 2, 3])).toEqual(["1", "2", "3"]);
   });
 });
 
 describe("uppercaseWordsInArray", () => {
-  xit("makes every string in the array uppercase", () => {
+  it("makes every string in the array uppercase", () => {
     expect(uppercaseWordsInArray(["cat", "mouse", "banana"])).toEqual([
       "CAT",
       "MOUSE",
@@ -96,7 +96,7 @@ describe("uppercaseWordsInArray", () => {
 });
 
 describe("reverseWordsInArray", () => {
-  xit("reverses every string in an array", () => {
+  it("reverses every string in an array", () => {
     expect(reverseWordsInArray(["cat", "Mouse", "banana"])).toEqual([
       "tac",
       "esuoM",
@@ -106,13 +106,13 @@ describe("reverseWordsInArray", () => {
 });
 
 describe("onlyEven", () => {
-  xit("filters the array and only returns even numbers", () => {
+  it("filters the array and only returns even numbers", () => {
     expect(onlyEven([1, 2, 3, 4, 5, 6, 7, 8])).toEqual([2, 4, 6, 8]);
   });
 });
 
 describe("removeNthElement2", () => {
-  xit("returns an array with the nth element removed, and does not mutate the original", () => {
+  it("returns an array with the nth element removed, and does not mutate the original", () => {
     const array = ["bike", "car", "train", "bus"];
     expect(removeNthElement2(2, array)).toEqual(["bike", "car", "bus"]);
     expect(array).toEqual(["bike", "car", "train", "bus"]);
@@ -120,7 +120,7 @@ describe("removeNthElement2", () => {
 });
 
 describe("elementsStartingWithAVowel", () => {
-  xit("returns elements starting with a vowel", () => {
+  it("returns elements starting with a vowel", () => {
     expect(
       elementsStartingWithAVowel([
         "apple",
@@ -153,7 +153,7 @@ describe("elementsStartingWithAVowel", () => {
     ).toEqual(["apple", "epple", "ipple", "opple", "upple"]);
   });
 
-  xit("is case insensitive", () => {
+  it("is case insensitive", () => {
     expect(
       elementsStartingWithAVowel([
         "Apple",
@@ -188,7 +188,7 @@ describe("elementsStartingWithAVowel", () => {
 });
 
 describe("removeSpaces", () => {
-  xit("returns the string with the space characters removed", () => {
+  it("returns the string with the space characters removed", () => {
     expect(removeSpaces("this string has spaces")).toEqual(
       "thisstringhasspaces"
     );
@@ -199,13 +199,13 @@ describe("removeSpaces", () => {
 });
 
 describe("sumNumbers", () => {
-  xit("returns the sum of the numbers in the array", () => {
+  it("returns the sum of the numbers in the array", () => {
     expect(sumNumbers([1, 3, 5, 6, 2, 8])).toEqual(25);
   });
 });
 
 describe("sortByLastLetter", () => {
-  xit("sorts the string by the last character", () => {
+  it("sorts the string by the last character", () => {
     expect(
       sortByLastLetter(["Lannister", "Stark", "Greyjoy", "Targaryen"])
     ).toEqual(["Stark", "Targaryen", "Lannister", "Greyjoy"]);
diff --git a/test/booleans.test.js b/test/booleans.test.js
index c0ae87b1..7a6e9c95 100644
--- a/test/booleans.test.js
+++ b/test/booleans.test.js
@@ -17,14 +17,14 @@ const {
 } = require("../src/booleans");
 
 describe("negate", () => {
-  xit("returns the opposite of the passed boolean value", () => {
+  it("returns the opposite of the passed boolean value", () => {
     expect(negate(true)).toBe(false);
     expect(negate(false)).toBe(true);
   });
 });
 
 describe("both", () => {
-  xit("returns true if both of the given values are true", () => {
+  it("returns true if both of the given values are true", () => {
     expect(both(true, true)).toBe(true);
     expect(both(true, false)).toBe(false);
     expect(both(false, true)).toBe(false);
@@ -33,7 +33,7 @@ describe("both", () => {
 });
 
 describe("either", () => {
-  xit("returns true if at least one of the given values are true", () => {
+  it("returns true if at least one of the given values are true", () => {
     expect(either(true, true)).toBe(true);
     expect(either(true, false)).toBe(true);
     expect(either(false, true)).toBe(true);
@@ -42,7 +42,7 @@ describe("either", () => {
 });
 
 describe("none", () => {
-  xit("returns true if neither of the given values are true", () => {
+  it("returns true if neither of the given values are true", () => {
     expect(none(true, true)).toBe(false);
     expect(none(true, false)).toBe(false);
     expect(none(false, true)).toBe(false);
@@ -51,7 +51,7 @@ describe("none", () => {
 });
 
 describe("one", () => {
-  xit("returns true if exactly one of the given values are true", () => {
+  it("returns true if exactly one of the given values are true", () => {
     expect(one(true, true)).toBe(false);
     expect(one(true, false)).toBe(true);
     expect(one(false, true)).toBe(true);
@@ -60,7 +60,7 @@ describe("one", () => {
 });
 
 describe("truthiness", () => {
-  xit("returns the truthiness of the given value", () => {
+  it("returns the truthiness of the given value", () => {
     expect(truthiness("")).toBe(false);
     expect(truthiness("dbbd")).toBe(true);
     expect(truthiness(0)).toBe(false);
@@ -74,7 +74,7 @@ describe("truthiness", () => {
 });
 
 describe("isEqual", () => {
-  xit("returns whether the two values are equal", () => {
+  it("returns whether the two values are equal", () => {
     expect(isEqual(true, false)).toBe(false);
     expect(isEqual(true, true)).toBe(true);
     expect(isEqual("true", "true")).toBe(true);
@@ -85,7 +85,7 @@ describe("isEqual", () => {
 });
 
 describe("isGreaterThan", () => {
-  xit("returns true if the first number is strictly greater than the second", () => {
+  it("returns true if the first number is strictly greater than the second", () => {
     expect(isGreaterThan(1, 2)).toBe(false);
     expect(isGreaterThan(3, 2)).toBe(true);
     expect(isGreaterThan(4, 4)).toBe(false);
@@ -93,7 +93,7 @@ describe("isGreaterThan", () => {
 });
 
 describe("isLessThanOrEqualTo", () => {
-  xit("returns true if the first number is less than or equal to the second", () => {
+  it("returns true if the first number is less than or equal to the second", () => {
     expect(isLessThanOrEqualTo(1, 2)).toBe(true);
     expect(isLessThanOrEqualTo(3, 2)).toBe(false);
     expect(isLessThanOrEqualTo(4, 4)).toBe(true);
@@ -101,7 +101,7 @@ describe("isLessThanOrEqualTo", () => {
 });
 
 describe("isOdd", () => {
-  xit("returns whether the number is odd", () => {
+  it("returns whether the number is odd", () => {
     expect(isOdd(5)).toBe(true);
     expect(isOdd(6)).toBe(false);
     expect(isOdd(7)).toBe(true);
@@ -110,7 +110,7 @@ describe("isOdd", () => {
 });
 
 describe("isEven", () => {
-  xit("returns whether the number is even", () => {
+  it("returns whether the number is even", () => {
     expect(isEven(5)).toBe(false);
     expect(isEven(6)).toBe(true);
     expect(isEven(7)).toBe(false);
@@ -119,7 +119,7 @@ describe("isEven", () => {
 });
 
 describe("isSquare", () => {
-  xit("returns true if the number is a square", () => {
+  it("returns true if the number is a square", () => {
     expect(isSquare(9)).toEqual(true);
     expect(isSquare(5)).toEqual(false);
     expect(isSquare(-4)).toEqual(false);
@@ -128,7 +128,7 @@ describe("isSquare", () => {
 });
 
 describe("startsWith", () => {
-  xit("returns whether the given string starts with the given character", () => {
+  it("returns whether the given string starts with the given character", () => {
     expect(startsWith("a", "aardvark")).toBe(true);
     expect(startsWith("a", "qaardvark")).toBe(false);
     expect(startsWith("a", "Aardvark")).toBe(false);
@@ -136,7 +136,7 @@ describe("startsWith", () => {
 });
 
 describe("containsVowels", () => {
-  xit("returns whether the given string contains vowels", () => {
+  it("returns whether the given string contains vowels", () => {
     expect(containsVowels("cat")).toBe(true);
     expect(containsVowels("DOG")).toBe(true);
     expect(containsVowels("why")).toBe(false);
@@ -144,7 +144,7 @@ describe("containsVowels", () => {
 });
 
 describe("isLowerCase", () => {
-  xit("it returns true if the given string is lowercase", () => {
+  it("it returns true if the given string is lowercase", () => {
     expect(isLowerCase("abc")).toBe(true);
     expect(isLowerCase("abc213")).toBe(true);
     expect(isLowerCase("Abc")).toBe(false);
diff --git a/test/numbers.test.js b/test/numbers.test.js
index 94e3bbfb..df3eb014 100644
--- a/test/numbers.test.js
+++ b/test/numbers.test.js
@@ -13,7 +13,7 @@ const {
 } = require("../src/numbers");
 
 describe("add", () => {
-  xit("adds the two numbers together", () => {
+  it("adds the two numbers together", () => {
     expect(add(2, 1)).toEqual(3);
     expect(add(15, 76)).toEqual(91);
     expect(add(12, 0)).toEqual(12);
@@ -22,7 +22,7 @@ describe("add", () => {
 });
 
 describe("subtract", () => {
-  xit("subtracts the second number from the first", () => {
+  it("subtracts the second number from the first", () => {
     expect(subtract(2, 1)).toEqual(1);
     expect(subtract(1, 2)).toEqual(-1);
     expect(subtract(-2, 1)).toEqual(-3);
@@ -32,7 +32,7 @@ describe("subtract", () => {
 });
 
 describe("multiply", () => {
-  xit("multiplies the two numbers together", () => {
+  it("multiplies the two numbers together", () => {
     expect(multiply(10, 3)).toEqual(30);
     expect(multiply(-11, 5)).toEqual(-55);
     expect(multiply(-4, -9)).toEqual(36);
@@ -40,7 +40,7 @@ describe("multiply", () => {
 });
 
 describe("divide", () => {
-  xit("divides the first number by the second number", () => {
+  it("divides the first number by the second number", () => {
     expect(divide(20, 5)).toEqual(4);
     expect(divide(5, 2)).toEqual(2.5);
     expect(divide(2, 5)).toEqual(0.4);
@@ -49,7 +49,7 @@ describe("divide", () => {
 });
 
 describe("power", () => {
-  xit("returns the first number to the power of the second", () => {
+  it("returns the first number to the power of the second", () => {
     expect(power(5, 2)).toEqual(25);
     expect(power(2, 3)).toEqual(8);
     expect(power(10, 5)).toEqual(100000);
@@ -57,7 +57,7 @@ describe("power", () => {
 });
 
 describe("round", () => {
-  xit("rounds the number to the nearest integer", () => {
+  it("rounds the number to the nearest integer", () => {
     expect(round(2.1)).toEqual(2);
     expect(round(9.7)).toEqual(10);
     expect(round(5.5)).toEqual(6);
@@ -65,7 +65,7 @@ describe("round", () => {
 });
 
 describe("roundUp", () => {
-  xit("rounds the number up to the nearest integer", () => {
+  it("rounds the number up to the nearest integer", () => {
     expect(roundUp(2.1)).toEqual(3);
     expect(roundUp(9.7)).toEqual(10);
     expect(roundUp(5.5)).toEqual(6);
@@ -73,7 +73,7 @@ describe("roundUp", () => {
 });
 
 describe("roundDown", () => {
-  xit("rounds the number down to the nearest integer", () => {
+  it("rounds the number down to the nearest integer", () => {
     expect(roundDown(2.1)).toEqual(2);
     expect(roundDown(9.7)).toEqual(9);
     expect(roundDown(5.5)).toEqual(5);
@@ -81,7 +81,7 @@ describe("roundDown", () => {
 });
 
 describe("absolute", () => {
-  xit("returns the absolute value of the number", () => {
+  it("returns the absolute value of the number", () => {
     expect(absolute(-1)).toEqual(1);
     expect(absolute(1)).toEqual(1);
     expect(absolute(0)).toEqual(0);
@@ -93,7 +93,7 @@ describe("quotient", () => {
   // the first by the second, without the remainder
   // 18 divided by 7 is 2 remainder 4 (or 2.571...)
   // so the quotient of 18 and 7 is 2
-  xit("returns the quotient from dividing the first number by the second number", () => {
+  it("returns the quotient from dividing the first number by the second number", () => {
     expect(quotient(10, 3)).toEqual(3);
     expect(quotient(18, 7)).toEqual(2);
     expect(quotient(77, 10)).toEqual(7);
@@ -102,7 +102,7 @@ describe("quotient", () => {
 });
 
 describe("remainder", () => {
-  xit("returns the remainder when dividing the first number by the second number", () => {
+  it("returns the remainder when dividing the first number by the second number", () => {
     expect(remainder(10, 3)).toEqual(1);
     expect(remainder(18, 7)).toEqual(4);
     expect(remainder(77, 10)).toEqual(7);
diff --git a/test/objects.test.js b/test/objects.test.js
index 6fc32339..4e5daf18 100644
--- a/test/objects.test.js
+++ b/test/objects.test.js
@@ -12,7 +12,7 @@ const {
 } = require("../src/objects");
 
 describe("createPerson", () => {
-  xit("creates an object with the given name and age properties", () => {
+  it("creates an object with the given name and age properties", () => {
     expect(createPerson("Fred", 79)).toEqual({
       name: "Fred",
       age: 79
@@ -26,7 +26,7 @@ describe("createPerson", () => {
 });
 
 describe("getName", () => {
-  xit("returns the name property of the object", () => {
+  it("returns the name property of the object", () => {
     expect(
       getName({
         name: "Fred",
@@ -37,7 +37,7 @@ describe("getName", () => {
 });
 
 describe("getProperty", () => {
-  xit("returns the given property", () => {
+  it("returns the given property", () => {
     expect(
       getProperty("age", {
         name: "Fred",
@@ -53,14 +53,14 @@ describe("hasProperty", () => {
     age: 79
   };
 
-  xit("returns true if the object has the given property", () => {
+  it("returns true if the object has the given property", () => {
     expect(hasProperty("age", fred)).toBe(true);
     expect(hasProperty("favouriteColour", fred)).toBe(false);
   });
 });
 
 describe("isOver65", () => {
-  xit("returns true if the person is aged over 65", () => {
+  it("returns true if the person is aged over 65", () => {
     const jim = {
       name: "Jim",
       age: 66
@@ -83,7 +83,7 @@ describe("isOver65", () => {
 });
 
 describe("getAges", () => {
-  xit("returns the ages of each person in the array", () => {
+  it("returns the ages of each person in the array", () => {
     const jim = {
       name: "Jim",
       age: 66
@@ -104,7 +104,7 @@ describe("getAges", () => {
 });
 
 describe("findByName", () => {
-  xit("returns the person with the given name", () => {
+  it("returns the person with the given name", () => {
     const jim = {
       name: "Jim",
       age: 66
@@ -126,7 +126,7 @@ describe("findByName", () => {
 });
 
 describe("findHondas", () => {
-  xit("returns a list of cars manufactured by Honda", () => {
+  it("returns a list of cars manufactured by Honda", () => {
     const car1 = {
       manufacturer: "Honda",
       year: 1997,
@@ -156,7 +156,7 @@ describe("findHondas", () => {
 });
 
 describe("averageAge", () => {
-  xit("returns the average age of the people in the list", () => {
+  it("returns the average age of the people in the list", () => {
     const john = {
       name: "John",
       age: 60
@@ -177,7 +177,7 @@ describe("averageAge", () => {
 });
 
 describe("createTalkingPerson", () => {
-  xit("returns a person who can introduce themselves", () => {
+  it("returns a person who can introduce themselves", () => {
     const bill = createTalkingPerson("Bill", 40);
     expect(bill).toEqual({
       name: "Bill",
diff --git a/test/strings.test.js b/test/strings.test.js
index b10d44e3..42140ebd 100644
--- a/test/strings.test.js
+++ b/test/strings.test.js
@@ -8,21 +8,21 @@ const {
 } = require("../src/strings");
 
 describe("sayHello", () => {
-  xit('returns "Hello world!" when passed "world"', () => {
+  it('returns "Hello world!" when passed "world"', () => {
     expect(sayHello("world")).toEqual("Hello, world!");
   });
 
-  xit('returns "Hello MCR Codes!" when passed "MCR Codes"', () => {
+  it('returns "Hello MCR Codes!" when passed "MCR Codes"', () => {
     expect(sayHello("MCR Codes")).toEqual("Hello, MCR Codes!");
   });
 
-  xit('returns "Hello fsghjdfkhgf!" when passed "fsghjdfkhgf"', () => {
+  it('returns "Hello fsghjdfkhgf!" when passed "fsghjdfkhgf"', () => {
     expect(sayHello("fsghjdfkhgf")).toEqual("Hello, fsghjdfkhgf!");
   });
 });
 
 describe("uppercase", () => {
-  xit("returns the uppercased string", () => {
+  it("returns the uppercased string", () => {
     expect(uppercase("abc")).toEqual("ABC");
     expect(uppercase("def")).toEqual("DEF");
     expect(uppercase("ghi")).toEqual("GHI");
@@ -30,7 +30,7 @@ describe("uppercase", () => {
 });
 
 describe("lowercase", () => {
-  xit("returns the lowercased string", () => {
+  it("returns the lowercased string", () => {
     expect(lowercase("ABC")).toEqual("abc");
     expect(lowercase("DEF")).toEqual("def");
     expect(lowercase("GHI")).toEqual("ghi");
@@ -38,7 +38,7 @@ describe("lowercase", () => {
 });
 
 describe("countCharacters", () => {
-  xit("returns the number of characters in the string", () => {
+  it("returns the number of characters in the string", () => {
     expect(countCharacters("fsfsgsfdg")).toEqual(9);
     expect(countCharacters("fsfsg")).toEqual(5);
     expect(countCharacters("")).toEqual(0);
@@ -46,7 +46,7 @@ describe("countCharacters", () => {
 });
 
 describe("firstCharacter", () => {
-  xit("returns the first character of the string", () => {
+  it("returns the first character of the string", () => {
     expect(firstCharacter("ABC")).toEqual("A");
     expect(firstCharacter("DEF")).toEqual("D");
     expect(firstCharacter("GHI")).toEqual("G");
@@ -54,11 +54,11 @@ describe("firstCharacter", () => {
 });
 
 describe("firstCharacters", () => {
-  xit("returns the first 4 characters of the string", () => {
+  it("returns the first 4 characters of the string", () => {
     expect(firstCharacters("sd32fg45", 4)).toEqual("sd32");
   });
 
-  xit("returns the first 2 characters of the string", () => {
+  it("returns the first 2 characters of the string", () => {
     expect(firstCharacters("asd", 2)).toEqual("as");
   });
 });