Microsoft Word does not have an option to translate documents automatically, if you have downloaded or received a document through email, you will need to copy the text and paste it in a online document and PDF translator or offline language translator to translate the text to your language.
The Doc Translate add-in for Microsoft Word will allow you to translate Word Documents through a new Ribbon Menu item.
Once you have installed the Office add-in, open the docTranslate menu and select the language you want to translate to, you can choose to add the translations inline, to a new document, in the same document or append it to the end of the document.
Doc Translate is powered by the Windows Live Translator Engine.
Note: The Doc Translate release page is in Portuguese, you may want to head directly to the translated page in English.