Change language
You can use your desktop and applications in any of dozens of languages, provided you have the proper language packs installed on your computer.
Click the icon at the very right of the top panel and select System Settings.
Click Language Support.
Select your desired language on the Language tab. Drag the language to the top of the list.
You have to log out and back in for language changes to take effect. Click the icon at the very right of the panel and select Log Out to log out.
Some translations may be incomplete, and certain applications may not support your language at all.
There are some special folders in your home folder where applications can store things like music, pictures, and documents. These folders use standard names according to your language. When you log back in, you will be asked if you want to rename these folders to the standard names for your selected language. If you plan to use the new language all the time, you should update the folder names.
You find more detailed guidance on languages and regional formats in Language Support Help.