The contextual classification engine is also capable of distinguishing the language of any given page. From the Brand Protection selection in the campaign editor's General tab, you can run your campaign only on pages that meet your language requirements.
Some available languages to target include: English, Dutch, French, German, Italian, Russian, Polish, Portuguese, and Spanish.
Note: You do not need to target a language if it is the official language of the country you are geotargeting. For example, if you target the United States, you do not need to add language targeting for English.