Change the language in my Libreoffice

I use Ubuntu 13.10 and I have installed Libreoffice by ppa.

But it is in english.

I want to change for portuguese.

How can I do this?

Do you want to change the graphical user interface or the spell checker?

LibreOffice uses the system default for the user interface. I guess you have installed Ubuntu in English, or?

I want to change graphical user interface

The help page for Languages details the required options, including one for the user interface.