Scripting Errors I cannot fix, Could use a helping hand and someone to tell me how to fix it:PART II

[pookiw]

Well for an assignment I was to fix a few scripts on my own. I managed to fix one fully by myself and another to only having a few errors which kind people on here helped me fix. Now Ive managed to get this final script down to the last few errors. (Going from 22 to 5 and being stuck) IF anyone is willing to assist me in fixing the errors and telling me what was wrong with them and how to fix it I would really be grateful. I’m very new to the scripting scene but I want to learn all I can!

public var health : int = 5;		// number of hits before game over
public var moveSpeed : int = 3;	// horizontal speed
public var jumpSpeed : float = 8;	// jumping speed
public var turnSpeed : float = 2;	// turning rate

private var controller : CharacterController;	// reference to CharacterController component
private var velocity : Vector;					// current speed

function Start ()
{

}

function Update ()
{
	// assume no input
	velocity.x = 0;
	velocity.z = 0;
	
	// forward
	if (Input.GetKey("w") || Input.GetKey("up"))
	{
		velocity + transform.forward * moveSpeed;
	}
	// back
	else if(Input.GetKey("s") || Input.GetKey("down"))
	{
		velocity + transform.back * moveSpeed;
	}
	// turn left
	if(Input.GetKey("a") || Input.GetKey("left"))
	{
		transform.rotate(0, -turnSpeed, 0);
	}
	// turn right
	else if(Input.GetKey("d") || ("right"))
	{
		Transform.Rotate(0, turnspeed, 0);
	}
	
	if(isGrounded)
	{
		// jump
		if(Input.GetKeyDown("space"))
		{
			velocity += transform.up * jumpSpeed;
		}
		else
		{
			velocity.y = 0;
		}
	}
	// gravity
	velocity += Physics.gravity * Time.deltaTime;
	// apply motion
	controller.Move(velocity * Time.deltaTime);

function onTriggerEnter()
{
	// detection radius
	if(trigger.name == "Enemy")
	{
		// set enemy to alert
		// Enemy is the name of the enemy script
		// alert is a variable on the Enemy script
		trigger.GetComponent(Enemy).alert = true;
	}
	// getting hit
	else if(trigger.name == "Body")
	{
		health--;
		if(health <= 0)
		{
			transform.DetachChildren();
			Destroy(gameObject);
		}
	}
}

function OnTriggerEnter(trigger : collider)
{
	// leaving detection radius
	if(trigger.name == "Enemy")
	{
		trigger.GetComponent(Enemy).alert = false;
	}
}

[Nachtmahr]

CharacterController was never assigned

Unity - Scripting API: Component.GetComponent

you do Calculation but no assignment
yourvar = yourDesiredValue;
Syntax Errors, wrong function names and Parameters take a look at

Unity - Scripting API: MonoBehaviour

like alucardj suggestet learn the basics and how to find and resolve Bugs. Use the Manual there full of Examples of Code usage.