semicolon problems

So i know this is a Frequently asked question but i just cant find a solution…

I have a small movement script(JS)

`
#pragma strict
var rotationSpeed = 100;

function Update () {
	var rotation : float = Input.GetAxis ("Horizontal") * rotationSpeed;
	rotation *= Time.deltaTime;
	rigidbody.AddRelativeTorque {Vector3.back * rotation};
}

`
it just says to me Error UCE0001: ‘;’ expected. Insert a semicolon at the end.
Any help?

Replace { } with () on rigidbody line

Can you fix My problem

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class look : MonoBehaviour
{

[Range(-90f, 90f)]
Quaternion rotation;

int Xrotate = 0;
[SerializeField]
KeyCode up;
[SerializeField]
KeyCode down;

// Update is called once per frame
void Update()
{
    if (Input.GetKey(up) && Xrotate > -90)
    {
        transform.Rotate(-2f, 0f, 0f);
        int Xrotate - 2;
    }
    if (Input.GetKey(down) && Xrotate < 90)
    {
        transform.Rotate(2f, 0f, 0f);
        int Xrotate + 2;
    }
}

}