19.congratulations, graduate.may all your dreams and plans turn to fulfillment and success.
祝賀你，畢業生。願你夢想成真，萬事如意。
20.heartiest congratulations upon your graduation.wishing you all the excitement, all the challenge, all the happiness life call hold.
21.i'm hopeful and confident that the graduation ceremony will really be a completely new start.i believe that the knowledge you have acquired will enable you to be successful in whatever field you may enter.
我希望，同時也相信，畢業典禮是你全新的開端。我深信，以你所掌握的知識，不管從事何種工作你都能大有作為。