How to turn this script?

I have a script to scroll:

var speed = 2.2;
var crawling = false;

function Start()
{

Screen.showCursor = true;
  
 }

function Update ()
{
    if (!crawling)
        return;
    transform.Translate(Vector3.up * Time.deltaTime * speed);
    if (gameObject.transform.position.y > .8)
    {
        crawling = true;
    }
}

And I have one questions, how to do after 10 seconds began to scroll in down ?

I have tried:

var speed = 2.2;
var crawling = false;

function Start()
{

Screen.showCursor = true;
  
 }

function Update ()
{
    if (!crawling)
        return;
    transform.Translate(Vector3.up * Time.deltaTime * speed);
    if (gameObject.transform.position.y > .8)
    {
        crawling = true;
    }
	
	yield WaitForSeconds(10);
	
	
	 if (!crawling)
        return;
    transform.Translate(Vector3.down * Time.deltaTime * speed);
    if (gameObject.transform.position.y > .8)
    {
        crawling = true;
    }
	
	
}

but this is not work :confused:

You cannot yield in Update(). I might approach this problem differently, but from where you are now, consider using Invoke(). You could do:

var speed = 2.2;
var crawling = false;
 
function Start() 
{
    Screen.showCursor = true;
    Invoke("Reverse", 10.0);
 }

function Reverse()
{
    speed = -speed;
}
 


function Update ()
{
      if (!crawling)
             return;
       transform.Translate(Vector3.up * Time.deltaTime * speed);
       if (gameObject.transform.position.y > .8)
       {
            crawling = true;
        }
  }