Cannot implicitly convert type void to UnityEngine.Vector3

So, I'm currently porting some js scripts from Unity3D examples to C#, and one of the errors I'm getting is this : Cannot implicitly convert type void to UnityEngine.Vector3

Here's a screenshot and the script by the way

 void Update () {
 
 //Character movement direction
        motor.movementDirection = Input.GetAxis ("Horizontal") * screenMovementRight + Input.GetAxis ("Vertical") * screenMovementForward;
        
        //Make sure the direction vector doesn't exceed a length of 1
        // so the character can't move faster diagonally than horitonally or vertically
        if (motor.movementDirection.sqrMagnitude > 1)
        {
            motor.movementDirection.Normalize();
        }
 
        //Character facing direction and screen focus point
 
        //First update the camera position to take into account how much the character moved since last frame
        //mainCameraTransform.position = Vector3.Lerp (mainCameraTransform.position, character.position + cameraOffset, Timpe.deltaTime * 45.0f * deathSmoothoutMultiplier);
 
 
        //Set up the movement plane of the character, so screenpositions
        //can be converted into world positions on this plane
        //playerMovementPlane = new Plane (Vector3.up, character.position + character.up * cursorPlaneHeight);
 
        //optimization (instead of newing Plane)
        playerMovementPlane.normal = character.up;
        playerMovementPlane.distance = -character.position.y + cursorPlaneHeight;
 
        //used to adjust the camera based on cursor
        Vector3 cameraAdjustmentVector = Vector3.zero;
 
        float axisX = Input.GetAxis("LookHorizontal");
        float axisY = Input.GetAxis("LookVertical");
        motor.facingDirection = ((axisX * screenMovementRight) + (axisY * screenMovementForward));
 
        cameraAdjustmentVector = motor.facingDirection;
 
        //On PC, the cursor point is the mouse position
        Vector3 cursorScreenPosition = Input.mousePosition;
 
        //Find out where the mouse ray intersects with the movement plane of the player
        Vector3 cursorWorldPosition = ScreenPointToWorldPointOnPlane (cursorScreenPosition, playerMovementPlane, mainCamera);
 
        float halfWidth = Screen.width / 2.0f;
        float halfHeight = Screen.height / 2.0f;
        float maxHalf = Mathf.Max (halfWidth, halfHeight);
 
        //Acquire the relative screen position
        Vector3 toMath = (halfWidth, halfHeight, cursorScreenPosition.z);
        Vector3 posRel = cursorScreenPosition - (Vector3 (halfWidth, halfHeight, cursorScreenPosition.z));
        posRel.x /= maxHalf;
        posRel.y /= maxHalf;
 
        cameraAdjustmentVector = posRel.x * screenMovementRight + posRel.y * screenMovementForward;
        cameraAdjustmentVector.y = 0.0f;
 
        //The facing direction is the direction from the character to the cursor world position
        motor.facingDirection = (cursorWorldPosition - character.position);
        motor.facingDirection.y = 0;
 
        //Draw the cursor nicely
        HandleCursorAlignment (cursorWorldPosition);
 
        //Handle camera position
 
        //Set the target position of the camera to point at the focus point
        Vector3 cameraTargetPosition = character.position + initOffsetToPlayer + cameraAdjustmentVector * cameraPreview;
 
        //Apply some smoothing to the camera movement  WTF IS "ref" in cameraVelocity
        mainCameraTransform.position = Vector3.SmoothDamp (mainCameraTransform.position, cameraTargetPosition, ref cameraVelocity, cameraSmoothing);
 
        //Save camera offset so we can use it in the next frame
        cameraOffset = mainCameraTransform.position - character.position;
 }