How do I make my Character Jump?

Hello, so I am following this tutorial on youtube on creating an endless runner for my 3D unity game. The video is very informal however the maker did not include a way for the character to jump. So I am asking is, is there a way to add a jump feature to the script I already have so far?

using UnityEngine;
using System.Collections;

public class PlayerMotor : MonoBehaviour 
{
	private CharacterController controller;
	private Vector3 moveVector;

	private float speed = 5.0f;
	private float verticalVelocity = 0.0f; 
	private float gravity = 12.0f;

	private float animationDuration = 3.0f;

	// Use this for initialization
	void Start () {
		controller = GetComponent<CharacterController> ();
	}
	
	// Update is called once per frame
	void Update () {

		if (Time.time < animationDuration) 
		{
			controller.Move (Vector3.forward * speed * Time.deltaTime);
			return;
		}

		moveVector = Vector3.zero;

		if (controller.isGrounded)
		{
			verticalVelocity = -0.5f;
		}
		else 
		{
			verticalVelocity -= gravity * Time.deltaTime;
		}

		// X - Left and Right
		moveVector.x = Input.GetAxisRaw ("Horizontal") * speed;

		// Y - Up and Down
		moveVector.y = verticalVelocity;

		// Z - Forward and Backward
		moveVector.z = speed;

		controller.Move (moveVector * Time.deltaTime);
	}
}

Well look this video remember to convert 2d to 3d
if you have any question feel free to ask

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