United added the Carling Cup yesterday to the Club World Cup.
Sir Alex Ferguson’s side are also seven points clear at the top of the Premier League, in the quarter-finals of the FA Cup and in a good position in the Champions League.
Ronaldo insisted: “It is quite difficult to achieve but we are going from game to game.
“We always have the opportunity to win everything. We’ve won this cup and now we don’t have much time to celebrate.”