Unexpected Token Gameobject

Hello,
im learning in unity 3d so im making easy game like slender, but in space with asronaut.

Im making code for fly up and down and i getting error:

Assets/_Scripts/Playerfly.js(3,8): BCE0043: Unexpected token: GameObject.

My script (JS):

#pragma strict
var boostFactor : float = 100; // or whatever
public GameObject Target;

function Start () {

}

function Update () {
	if ( Input.GetButtonDown("Fire1") ) {

	 	target.rigidbody.velocity += target.transform.up * boostFactor;

	}
	
	if ( Input.GetButtonDown("Fire2") ) {

	 	target.rigidbody.velocity += target.transform.down * boostFactor;

	}
}

The (3,8) in the middle of the bug report tells you that line 3 has the problem. You appear to be missing the var keyword which Javascript uses to declare variable names. Further, GameObject is a type, and so comes after the variable name and after a colon, just like you have on line 2.

Fine, but i get another error:
Assets/_Scripts/Playerfly.js(3,15): UCE0001: ‘;’ expected. Insert a semicolon at the end.

But there is semicolon

Code:

#pragma strict
var boostFactor : float = 100; // or whatever
var GameObject Target;

function Start () {

}

function Update () {
	if ( Input.GetButtonDown("Fire1") ) {

	 	target.rigidbody.velocity += target.transform.up * boostFactor;

	}
	
	if ( Input.GetButtonDown("Fire2") ) {

	 	target.rigidbody.velocity += target.transform.down * boostFactor;

	}
}