What is missing in the code?

const teachers = [
    {
        name: 'Ashley',
        topicArea: 'Javascript'
    }
];


const courses = ['Introducing JavaScript',
                'JavaScript Basics',
                'JavaScript Loops, Arrays and Objects',
                'Getting Started with ES2015',
                'JavaScript and the DOM',
                'DOM Scripting By Example'];


var i = courses.length;

/*

CHANGE 1: 
    Moved the 'newTeachers' object array higher in the code.
    You must declare 'let' variables BEFORE its implementation.

*/
let newTeachers = [
    {
        name: 'James',
        topicArea: 'Javascript'
    },
    {
        name: 'Treasure',
        topicArea: 'Javascript'
    }
];

/*

CHANGE 2: 
    Changed the name of the 'addNewTeachers' argument so that you know
    when the argument is being utilized vs an outside 
    variable. Keeps things less confusing.

CHANGE 3:
    Changed what you had 'teachers.lenght' to 'newTeachers.length'.
    What you had originally, had a spelling error in "length" as well as
    it was referencing the wrong array. Using 'teachers.length' would 
    always return '1' (because only one teacher is in the list at the start) 
    so it would only add one teacher.

    Secondly, 'newTeachers' is the object array you want to reference
    because it has the two new teachers you want to add to the main
    array of teachers. So we want to get the length of THIS array so
    we get the right amount of additions to the main list (which is 2).

CHANGE 4:
    Added 'addTeacher[j]' within the argument of the 'push' array method.
    Originally, you weren't pushing anything to new main teachers list as
    the push method was empty.

    What I've added within the push method will pull the object from the 
    'newTeachers' array according to the value that 'j' is set to and add 
    it to the main 'teachers' array. And this will only increment by 2 
    because we are getting the length of the 'newTeachers' array, which is 
    only 2 (because there are two objects in the array).

*/

// TODO: write a function that adds new teachers to the teachers array 
function addNewTeachers(addTeacher) {
  for (let j = 0; j < newTeachers.length; j++) {
    teachers.push(addTeacher[j])
  }
}

// TODO: fix this function so that it prints the correct number of courses and   teachers
function printTreehouseSummary() {
  for (let i = 0; i < teachers.length; i++) {
     console.log(`${teachers[i].name} teaches ${teachers[i].topicArea}`);
    }

  console.log(`Treehouse has ${i} JavaScript courses, and ${teachers.length} Javascript teachers`);
}


addNewTeachers(newTeachers);
printTreehouseSummary();