That's great, Congratulations!

太棒了，恭喜你!

Let me congratulate you on your promotion¹.

恭贺你升迁。

Congratulations on your new son!

恭喜你又添贵子!

I must congratulate you.

我得恭贺您。

I'm very happy for you.

真为你高兴。

You deserve it.

这是你应得的。

Let me congratulate you.

请允许我向你表示祝贺。

May I congratulate you.

我祝贺你。

Congratulations on winning the contract!

祝贺你获得了这个合同!

I'd like to congratulate you on your success.

我想对你的成功表示祝贺。

I wish you the same.

向您致以同样祝贺。

I am just very lucky.

我仅仅是很幸运罢了。

Thank you, but it is not really all that good.

谢谢你，不过我确实没那么好。