Composed of three times ten, or of twenty-nine plus one.

三十的。

The number consisting of three tens.

三十。

A sign representing thirty units, as 30 or xxx.

三十的符号(如 30 或 XXX )。

The numbers from 30 to 39.

[the ~ies] 30 至 39 的数目。

The years from 30 to 39 in a century or a lifetime.

[the ~ies] (年龄) 30 至 39 岁间；(世纪) 30 年代。