ActionScript 3.0 :: Error 1120 - MaskMovie Is Undefined Property

This is one of the errors.. it says the input is an undefined property
var finalDestination:Number = input.x;
var distanceMoved:Number = 0;
var distanceToMove:Number = Math.abs(finalDestination-currentPosition);
var finalSpeed:Number = .3;
var currentSpeed:Number = 0;
var dir:Number = 1;

This is the other error.. same thing, but maskMovie is the undefined property. I dont get it
function onEF(e:Event):void {
currentSpeed=Math.round(distanceToMove - distanceMoved + 1 * finalSpeed);
distanceMoved+= currentSpeed;
contentHold.x+= dir * currentSpeed;
if (Math.abs(distanceMoved - distanceToMove) <= 1) {
[Code] .....