tell me whats wrong with this lerp

im getting this error Assets/Scripts/time.cs(42,57): error CS1502: The best overloaded method match for UnityEngine.Vector3.Lerp(UnityEngine.Vector3, UnityEngine.Vector3, float)' has some invalid arguments and this one Assets/Scripts/time.cs(42,57): error CS1503: Argument #1' cannot convert UnityEngine.Transform' expression to type UnityEngine.Vector3'

 using UnityEngine;
 using System.Collections;
 
 public class time : MonoBehaviour {
     public float timescale = 1;
     Transform MyTf;
     float speed = 1f;
     float dist;
     float timestart;
     float length;
     float frac;
     public Transform  pos;
     public Transform pos1;
 
     // Use this for initialization
     void Start () {
         MyTf = transform;
     }
     
     // Update is called once per frame
     void Update () {
         length = Vector3.Distance (pos.position, pos1.position);
         dist = (Time.time - timestart)* speed;
         frac = dist / length;
         Time.timeScale = timescale;
 
     if(Input.GetKeyDown("2")){
             timescale = 1;
             Time.fixedDeltaTime = 1f * 0.02f;
 
         }
 
         if(Input.GetKeyDown("1")){
             timescale = 0.15f;
             Time.fixedDeltaTime = 0.15f * 0.02f;
             }
 
     if(timescale == 0.15f){
             if(Input.GetKeyDown("q")){
                 timescale = 1;
                 Time.fixedDeltaTime = 1f * 0.02f;
                 MyTf.position = Vector3.Lerp(pos , pos1 , frac);
             }
         }
         if(timescale == 0.15f){
             if(Input.GetKeyDown("e")){
                 timescale = 1;
                 Time.fixedDeltaTime = 1f * 0.02f;
             }
         }
     }
 }

i would very much appreciate any help thanks