how to fix this if statement?

am working on a tic tac toe game and am following an internet tutorial but while am reproducing the code this error appear in my if statement :

this is the error message:

Binary operator '&&' cannot be applied to two Bool operands

   @IBAction func buttonClicked(sender: UIButton) {

    if !plays[sender.tag] != nil && !aiDecided != nil && !done != nil {

       setImageSpot(sender.tag, player: 1)
    }
}