You say 'Congratulations' to someone in order to congratulate them on something nice that has happened to them or something good that they have done.
Congratulations, you have a healthy baby girl.
恭喜你,有个健康的千金宝宝!
Congratulations on your interesting article.
祝贺你,文章写得很有趣!
If you offer someone your congratulations, you congratulate them on something nice that has happened to them or on something good that they have done.
The club also offers its congratulations to D. Brown on her appointment as president.
俱乐部还就布朗被任命为会长一事向她表示了祝贺。