When you have multilingual content not in the Original language Bilingual content is fine, but what do you do in Drupal 8 when you have content only in a secondary language. I've got a site in English &amp; Japanese, with pages mostly in English (Original language), but some pages only in Japanese.
How to create content in a secondary language:

Go to the language settings of a content type and change it from "Site's default language (English)" to a secondary language or enable


  [x] Show language selector on create and edit pages


so that the editor can select a different language for each piece of content. As long as you don't add a translation to this content it stays monolingual (in the secondary language). You can even restrict a content type to this by disabling:


  [ ] Enable translation