Either the twenty eighth or the thirtieth is fine.

28号或30号都行。

Well, why do not we make it the thirtieth?

嗯，那我们就定30号吧。

The Swan Lake on our campus was built for the thirtieth anniversary.

校园里的天鹅湖是为建校30周年而建。

He left for New York and was inaugurated there on April thirtieth.

他前往纽约，并于4月30日宣誓就职。

In point of fact, he had just turned his thirtieth year.

实际上他也不过刚刚超过三十岁。

Of course, this doesn't mean that in olden days everyone dropped dead on their thirtieth birthday.

当然，这并不意味着以前的人在三十岁生日那天就会去世。

Originally, I planned to have a big party to celebrate my thirtieth.

本来我打算举办一个盛大的聚会来庆祝我三十岁。

Everyone says that your thirtieth birthday is very important.

大家都说三十岁生日很重要。

None of my forefathers have survived their thirtieth year.

我的祖先没有一个活到三十岁。

Now, he had already passed his thirtieth year, and had neither sowed nor reaped.

现在，他已经年过三十，既没有播种，也没有收获。