I need help with C#

i need help converting my java script code into c# can anyone help me? below is what ive converted into c# from java script.

using UnityEngine; using System.Collections;

public class Ballcontrol : MonoBehaviour { public int rotationSpeed = 100; public int jumpHeight = 8; private bool playOnce = true; public AudioClip Hit01; public AudioClip Hit02; public AudioClip Hit03; private bool isFalling = false;

 // Use this for initialization
 void Start () {
 
 }
 
 // Update is called once per frame
 void Update () {
     {
         //Handle ball rotation.
         rotation : float = Input.GetAxis ("Horizontal") * rotationSpeed;
         rotation *= Time.deltaTime;
         rigidbody.AddRelativeTorque (Vector3.back * rotation);
         
         if (Input.GetKeyDown(KeyCode.W) && isFalling == false)
         {
             rigidbody.velocity.y = jumpHeight;
             playOnce = True();
         }
         isFalling = true;
     }
     
     void OnCollisionStay ()
     {
         if (playOnce == true)
         {
             var theHit = Random.Range(0, 4);
             if (theHit == 0)
             {
                 audio.clip = Hit01;
             }
             else if (theHit == 1)
             {
                 audio.clip = Hit02;
             }
             else {
                 audio.clip = Hit03;
             }
             audio.pitch = Random.Range (0.9,1.1);
             audio.Play();
             playOnce = false;
         }
         isFalling = false;
     }
     
     void playOnceTrue () {
         yield return new WaitForSeconds(0.2);
         playOnce = true;
     }
 
 }

}