Wallrun script errors

Hi I made a script but I’m receiving errors (probably because of something silly like a curly bracket :P) I cant seem to fix or find so I would like some help with that but also, what they mean so if it happens again ill be ready! (error cs1525, cs1041 and cs8025)

using UnityEngine;
using System.Collections;

public class Wallrun : MonoBehaviour 
{
	public float collider;
	public float moveSpeed;
	WalkScript walk; 
	Camera player;

	void awake() 
	{
		walk = GetComponent<WalkScript> ();
	}

	// Update is called once per frame
	void update()
	{ 
		function OnTriggerEnter (other : collider) {
			walk.enabled= false; 
			transform.Translate (Vector3.forward * moveSpeed * Time.deltaTime);
		}
			function OnTriggerexit (other : collider) {
			walk.enabled = true;
		}
	  }
   }

	
}

One too many curly brackets in the update function!