My Eneny AI Script Wont Work?

Hey, here is my script for my enemy ai

 UnityEngine.Transform
 UnityEngine.Renderer
 
 var Distance;
 var Target : Transform;
 var lookAtDistance = 17.0;
 var attackRange = 10.0;
 var moveSpeed = 3.0;
 var Damping = 4.0;
 
 function Update ()
 {
     Distance = Vector3.Distance(Target.position, Transform.position);
     
     if(Distance < lookAtDistance)
     {
         Renderer.material.color = Color.green;
         lookAt();
     }
     
     if(Distance > lookAtDistance)
     
     {
         Renderer.material.color = Color.blue;
     }
     
     if(Distance < attackRange)
     {
         Renderer.material.color = Color.red;
         attack ();
     }
 }
 
 function lookAt ()
 {
     var rotation = Quaternion.LookRotation(Target.position - transform.position);
     Transform.rotation = Quaternion.Slerp(transform.rotation, rotation, Time.deltaTime * Damping);
 }
 
 function attack ()
 {
     Transform.Translate(Vector3.forward * moveSpeed * Time.deltaTime);
 }