You can change the default Office language to any other language available as a LIP (or language pack). The process to install language pack is easy. You just need to purchase or download the language pack (see here for more information about translating your Office) and then run the installer. To learn more about how to change the default Office language you can read our related article.
Choose the desired option, ie Microsoft Office Language Pack 2010 – English and then submit Continue.
Then click Install Now. Then wait until the process ends.
Finally click Close button and then you are ready to open your Office application using the new language.
In this case we opened Microsoft PowerPoint and we can see it is now translated to English.
This tutorial explains how to install the English language pack for Office 2010. You can install any other different language rather than English or your default language, and at the same time keep both languages. Then you can easily change the language in powerpoint. Read more about Language Packs here.