Changing the system languages in Mac OS X are really easy. So if your friends or parents aren’t comfortable with your English system, you can always switch the language to suite their needs.
Here is a step by step guide that will show you how to change the system language in Mac OS X.
1. Click on “Apple Logo“ and then click on System Preferences
2. In System Preferences. click on the Language & Tex icon.
3. Her you can change the system language from (in this case) Norwegian to English. All you have to do is to change the language order by dragging the English on top of Norwegian. Now log out and back in again (or reboot your Mac) and the language will be changed.